4 home design

8/8/2019 4 Home Design

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Chapter 4Energy-Efficient Home Design

Cost Codes: R = reducedN = negligibleS = small ($0.25 and $1.00/ft2 of floor area)

Recommendations

1. Have long axis east-west ( long sidesface north and south).2. Eliminate unnecessary windows.3. Have few or no east or west windows.4. Provide porches or other structuralshading.5. Have at least half of glass on southside (Central, Nort h Florida); considerclerestory or dormer windows.6. Have overhangs on all sides (considerhip roofs instead of gable roofs).7. Use simple building shapes.

8. Cross-ventilate major rooms (kitchen,dining, family, master bedroom).9. Place morning rooms on west side,afternoon rooms o n the east, livingareas o n n orth or south (time-of-daylayout).10. Locate air handler and ducts incondi tioned space, laundry area andwater heater in non-conditioned space.11. Avoid fireplaces.

Maximum Combined Total

FirstCost

N

RR/N

S/M/H

N

SR/N

N/S

N

N

R

H

OtherBenefits

-lncreasedcomfortOutdoorlivingareaslmprovedlightlevelsRain pro-tectionQuickercon-struction

ImprovedairqualityGreatlyenhancedcomfort--

l creasedcomfort

OIOEstimatedCooling

0-15

10-205-155-25

-5-1 00-5

10-20

0-5

0-10

0-10

SavingsHeating

10-50

10--

30-70

-0-20

-0-1 0

0-15

5-1570I


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Marketing Energy-Eff icient Home DesignMost ho me buyers are more concerned with thebasic rooms a house contains than with its energyfeatures. Nevertheless, you have an advan tage overthe competition by selling the potential buyer on theenergy advantages of your hom e plans. Manyenergy features can be in cluded a t a negligible costto you. Emphasize the comfort, convenience andsavings they provide.Orientation is a key energy and comfort feature.Chapter 3 on site planning illustrates the discomfortof eating an early-evening meal in a dining roomwith west-facing glass or a west-facing porch,because of the sun's strong rays at that time of day.Examples like that will help you market the time-of-day layout concept discussed in this chapter. Th eavoidance of west windows can be marketed firstfrom a comfort viewpoint, then from an energyviewpoint.

Daily Solar Heat Gain for 118" Single Glass

North South East Roof North South East Roofn. A.

west "rWest

Glass facing norrh or south is preferable toglass facing east, west or roofward (horizontal).It is clear that north and south windows cause signif-icantly fewer problems in sum mer than d o east orwest windows. Further, south windows are abenefit in winter. In North or Central Florida, youshould prom ote the wintertime heating that thesouth-facing glass will prov ide - lmost 2-1 /2times as much as the heating benefit of east or westwindo ws. For this reason, south-facing glass shouldbe clear, and shading should be provided by decidu-ous trees, overhangs (the calculation proc edure inthis chapter may be used to impress customers), andinterior operable window treatments (shades or

blinds). Sou th-facing clerestory window s are anexcellent means of providing light and winter heat tointerior spaces- nd in summer they receive only20% of the heat of a horizontal skylight! Add ition-ally, the dramatic effect of a clerestory, from insideand out, may actually sell the house.The passive solar heating afforded by proper win-do w o rientation can b e best utilized if it can be(1 ) distributed (via lots of openings between rooms)and (2) stored for use at night. Th e heat storageability (capacity) or "thermal mass" of the housedepends on the compon ents it is made with. Th efollowing components have good heat storage abilityand are referred to as being "massive":

a quarry tile concrete slab floora concrete block or brick interior partition walla concrete block exterior wall insulated on theoutside.

Ceramic or quarry tile flooring is the most marketa-ble feature, particularly in a high-end hom e. SeeChapters 5 and 6 for more details on marketing thethermal mass.Natural ventilation is a key energy-saving strategyfor Florida homes. Unfortunately, many stockhouse plans do not provide for cross-ventilation andwill require modifications. If you hav e selected ormodified plans that permit cross-ventilation, marketthem from the perspective of energy savings, "natu-ral living" and fresh air. Co mb ined with the effectsof thermal mass and ceiling fans, the air-conditioning savings from natural ventilation can be10-40%.Porches are desirable to many hom e buyers, so whynot incorporate on e in your h ome plans from thestart? This way, the porch roof can be continuousand there can be a radiant barrier and a vented atticabove the porch (techniques described in Ch apter8). Point ou t that a porch on the east or south sideprovides a shaded, breezy haven during the heat oflate summ er afternoons and evenings. Considermore than on e porch for larger homes. O n starteror retirement hom es, explore the market (and cost)trade-off of a porch vs. the extra bedroom - rmak e the porch an option. Since a porch is far bet-ter than a fireplace in terms of energy savings,encourage the choice of the porch by asking homebuyers which they will use more.


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Selecting and Modifying Home Plansfor ~ n e r g ~f f i c i e n c iThe rest of this chapter describes energy-efficient A house plan which has a narrow front is best for afeatures to look for in a home plan, and provides site which faces east or west. Many zero lot line andexamples that will help you visualize "putting it all other narrow front plans are now available.together."1. Have long axis east-westThe best time to start thinking of this is in the subdi-vision and site planning stage. How ever, most siteswill accomm odate a h ouse oriented in this fashion- hat is, with its long sides facing north and south.Suppose a 1500-square-foot house and a 500-square-fo ot garage w ere going on a site. If the sitefaces north or south an d is a 100-foot by 100-footlot. a conventional solution is:

Narrow house shape is best foreast- or west-facing lots.Side-entry garages can help relieve the im pression ofthe garage dominating the street side elevation.Oth er specific solutions to west fronts and east frontsare covered in exam ples at the end of this chapter.2. Eliminate unnecessary windowsW indo ws generally represent a source of significantheat gain in sum mer an d significant heat loss in w in-Ideal orientation of a Florida house. ter. Proper orientation of the windows and selection

Or on a 75-foot by 100-foot lot which can not have of approp riate glass (see Chapter 7) can p artiallymore than a 54-foot-wide footprint: alleviate the problem. How ever, excessive glass maynot be adding much value to the home. As a gen-eral rule, 15%of the floor a rea given to well-spacedwindo ws will provide a well-lit interior. But if yougive that much or more percentage to windows,make su re the glass is well shaded and/ or considermore elaborate window products (see Chapter 7).Homes can be attractive with 10% or less of floorarea as w indow glass, and som e builders are findingthat the initial cost-savings of fewer w indow s canprovide an edge on the competition. Choose plansthat have a few well-placed windows in terms ofview, appearance a nd energy considerations insteadof many randomly placed windows.

Orientation for standard size lots.


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Selecting and Modifying Home Plans

3. Have few or no east or west windo wsFor a north- or south-facing lot, there are a numberof plans which omit side windows that face east orwest. An obv ious alternative is to place a garage orcarpo rt on o ne of these sidesof the house. For east- or Porch]west-facing lots, choose house Porch toplans that hav e just one frontwindow and one or moreporches (back a nd front).

windows windows

I 1-One or no windows(Front of house)

Avoid unshaded east- or west-facing windows.4. Provide porches or otherstructural shadingSince east and west windows have significantlymore solar heat gain in summer than north or sou thwindows, permanent window shading using porchesor building shape is desired. Shad ing from the westsun is even more important than from the east sun,du e to the time of day. Keep buffer spaces (closets,the garage, etc.) on the east an d west sides.A porch provides a place for the home's occupantsto eat and even cook outdoors, assuming it is shady,breezy and insect-free. Since heat from food andbodies remains outside, a porch can be an imp ortantenergy saver worth looking for in home designs. T oencourage the use of the porch for outdoor dining,choose a home plan that incorporates the followingdesign criteria. -------1I

Screen Iporch IIwbE

s

This north-facing porch will be shadedfrom summer evening sun.

Orient the porch so it is shaded in the evening insumm er. The east and south sides are firstchoices. A north-facing porch w ill receive directsun from the northwest, so an "L" to the west isrequired for shading (see drawing). A west-facingporch can provide nice shade for the house b ut

Place a porch on east and west sides.will probably not be used in the evening. Havingtwo porches - ne on the east side and o ne onthe west side - ssures a shady porch is availableall day long.Have direct access from the kitchen to the porch.Having to carry dishes through a dining room orfamily room discourages the frequent use of aporch for dining. Atrium (Fren ch) or slidingglass doors directly to the porch will provideadded convenience.

Opening from another room 7C

I1 KITCHEN - 116x12 SCREEN IPORCH I

- - r - - 3 - - 7 II4SCREEN I

PORCHII

. - - 1 - - 3 - - A

0 00 0

KITCHEN

IoolConvenient access from kitchen

to porch is desirable.

r

IIh


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Mak e sure the porch will be cross-ventilated. in two conventional ways. On e is to use a goodThree open sides is best. In som e cases, open conducting material on the slab floor (tile or slate,house windows will permit cross-ventilation of a for exam ple) and the other is to use concrete blockporc h. A ceiling fan can help people feel cool. or brick partition walls. For every square foot ofsouth glass, there should be 30 Btu (British T herma lUnit, a unit of ener gy) per OF of storage. A 4-inchslab floor has 8 Btu/OF per square foot. An 8-inchblock wall has 30 Btu/OF per square foot of wallarea. So, glass area (GA) = partition wall block area+ (4/ 15 x tiled concrete slab floor area). Anotherway of putting that is: use 3.7 5 squa re feet ofexposed slab for each square foot of south-facingglass.For example, suppose you wanted to use a housedesign with 300 square feet of glass and you modi-fied it so 200 square feet of glass was on the southside. You would then w ant one of the following:200 square feet of 8-inch block partition wall (25feet of 8-foot-high wall)750 square feet of tiled floor (See Chapter 5 forother options)a combination such as 100 square feet of blockwall and 375 square fcet of tiled area.Another alternative is to use containers of water aswall dividers. There ar e cylindrical containersdesigned for this purpose, an d the water can be d yedfor an aesthetic effect. W ater provides 62 Btu per

Install ceiling fans on porches. cubic foot (8 Btu/gallon = 1 ~ t u / ~ o u n d ) .Keep the roof of the porch cool. Use a ventilated Elements of successfulattic space and a radiant barrier over the porch as passive solar heating for Floridadescribed in Chapter 8.

Other structural shading techniques can be provided.Overh angs (described later in this chapter) areimpo rtant. In two-story homes, use designs whichprovide overhangs o r other shading for first-floorwindows. North-facing windows are best shaded byadjacent projections, such as a garage that sticks out.Recessing the windows on the north side is anothergood shading method.

5. Have at least half of glasson south sideAs illustrated by the chart in the marketing section,south-facing glass receives significant winter sun andmuch less summ er sun. In North and CentralFlorida, use south-facing window s to provide heat in Combine all elements to use thewinter. Place the main living area on the south side. sun's heat in winter.Provide heat storage in the house to prevent ov er- With concrete block construction, use block wallsheating. In frame houses on slabs, this can be don e with R-1 exterior insulation (see Chap ter 6).


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Heating Savings for a Well-Sealed Home with R11 Walls,Double Glass Windows and High Mass

Also, use openab le window s, not fixed glass, as aback up to prevent overheating. Position the houseon the site so the south window s will not be shadedby adjacent buildings or evergreen trees.

PercentHeatingSavings

3040506070

How much energy can you save by doing this? Thatdepends, of course, on the house itself and thenum ber of people occupying it. Fo r a family offour, the preceding table shows the percentage ofheating saved for different fractions of glass area.Starting in the design stage, the only extra cost of thepassive solar heating is a floor finish that will permitthe concrete slab to be exposed for use as a thermalmass. Th e energy conservation measures are theequivalent of the baseline house in the energy code(including a t least Level 2 air-tightening and double-pane w indows). And it is no m ore costly to situateglass on the south side. Trying to provide mor e than50%heating savings may no t be cost-effective due tothe required window area.Ther e are also s ome initial cost savings in providinga passive solar heating design. Yo u may be able tosubstitute electric strip heat for a heat pump . Heatwill be required primarily during very cold nights(when a heat pum p wo uld rely mainly on electricresistance heat an ywa y) o r cold overcast periods(infrequent in Florida).

North Florida(R30 ceiling insulation)

In Florida, solar heating is secondary to cooling. D onot add window area for the sake of heating.Instead, shift window area from east and west sidesto the south side.

Central Florida(R19 ceiling insulation)

Required south glassas percentage ofconditioned floor

space5.38.1

11.5Not recommendedNot recommended

D O not use attached "sunrooms" or greenhouses thathave overhead glass. This glass receives too mu chsun in sum mer, is difficult to shade, an d is notopenable.

Required south glassas percentage ofconditioned floorspace

3.35.17.29.8

13.3

Required exposedslab floor area aspercentage of con-ditioned floor space203 143

Not recommendedNot recommended

Clerestory or Dormer Windows. Look into designswhich have north-facing o r south-facing clerestoryor dormer windows. These window s can providedaylight to interior spaces at a fraction of the heatgain of skylights (and with less chance of leakingrain). The y can provide a dram atic effect inside andout which m ay help you sell the home . Clerestorywindows should be o perable (awning-type orhopper-type) to provide a secure ventilation outlet.If operable, they can be used to ventilate a roo mthat otherwise would not have cross-ventilation.South-facing clerestory windows can be used toprovide solar heating to rooms o n the north side (seeend-of-chapter examples). Moreo ver, because thedirection of the slope of a shed roof is unlike that o fa no rmal overhang, all south-facing clerestory w in-dows can be used for winter heat gain and still betotally shaded in summer from the direct sun (asshown o n next page).

Required exposedslab floor area aspercentage of con-ditioned floor space1219273750

Clerestory windows can provideshaded daylight.


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6. Have roof overhangsSearch for house plans that provide o verhangs on allsides of the house (hip roof). Make certain that theroof is oriented along an east-west axis if the plancalls for a gable roof. Th e resultant overhang o n thesouth side will shade all direct sun during thesummer. The ideal length of an overhang on thesouth side of a house is dependent on three factors:the latitude of the locationthe time of year shade is desiredthe distance between the soffit and the bottom ofthe glass.It is quite simple to calculate the ideal length of ahorizontal south overhang using the table below.

For south-facing clerestory windows, the roof whichwill shade the window is often rising and the multi-plication factors are less appr opriate . Therefore, sunangles a an d b are also shown for each city. Thepoint where a and b cross is the ideal location forthe end of the roof as shown. Dra w the roof line,window , and angles a and b to scale to determinethis point.Although all overhang factors are for south-facingsurfaces only, overhangs can be effective in shadingall sides from diffuse sunlight. How ever, unlike thesouth side, "direct beam" solar heat will fall on aneast, west or north side under an overhang du e tothe low angle of the sun. Use overhangs as wide aspractical on north, east and west sides.

7-DLThe length (L) of a south-facing overhang

can be determined by knowing thesill-to-soffit distance (D).Angle a is Dec. 21 sun, angle b is end of winter(see table below for dates).

Overhang Design for South-facing Windows

Latitude

25"26'27"28'29"3031"

Location

The KeysMiamiJupiterTampa

New SmyrnaBeach

PanamaCity

Graceville

~i~~ of year ~ ~ ~ ~ l l ~Shaded fromDirect Sun

Feb 17 - Oct 24Feb 24 - Oct 16Mar 5 - Oct 7Mar 7 - Oct 5

Mar 16 - Sep 27Mar 21 - Sep 21Mar 30 - Sep 13

Factor(F).77.73.69.65.61.58.54

Sun Anglesa b

41.540.539.538.537.536.535.5

52.554.053.557.058.560.061.5

Length of Overhang (L= DxF) forSill-to-Soffit D istance (D ) of:

4'3.1'2.9'2.8'2.6'2.4'2.3'2.2'

5'3.9'3.7'3.5'3.3'3.1'2.9'2.7'

6'4.6'4.4'4.1'3.9'3.7'3.5'3.2'

7'5.4'5.1'4.8'4.6'4.3'4.1'3.8'

8'6.2'5.8'5.5'5.2'4.9'4.6'4.3'


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7. Use simple building shapesA rectangular-shaped home oriented on an east-westaxis is the best design for energy efficiency. Asquare is better than a rectangle oriented no rth-south. Designs which have a large amou nt of exte-rior wall area should be avoided.However, windows are more important than walls.An extra "jog" in the house shape to permit a win-dow to face north or south instead of east or westwill usually be a good trade-off and result in loweryear-rou nd energy use. Also, cross-ven tilation ofrooms lends itself nicely to sp read-out, one-room-deep houses. If properly des igned, the benefits ofgood cross-ventilation and orientation should out-weigh the extra energy load imposed by slightlymore wall area.Two-story designs have more wall area and lessfloor and roof a rea than simple one-story designs.They are also more difficult to shade with landscap-ing. There fore, consider using better-insu lated wallson two -story designs. Two-story h ome designs fre-quently can be modified easily for adequatecross-ventilation.8. Cross-ventilate roomsBefore vapor-compression air conditioning, naturalventilation kept hom eown ers cool. Florida houseswere built with wide porches and large windows.Th e principles inherent in these older homes can beapplied to contem porary ones. New hom es can alsobe designed with massive materials to "store" thecooling provided by n ight-time ventilation an d use itthe next day to augment air conditioning.Th e key to natural ventilation design is allowingopenings for the air to enter and leave the home.

Allow openings for air to enter andleave the home.

Ideally, all rooms should be cross-ventilated. Thisincludes bedrooms w hen their doors are shut. How -ever, the major living, eating, sleeping an d foodpreparation areas are most important. The kitchenis a source of much heat (from the refrigeratormotor, dishwasher, oven, stove and microwave), sochoose designs where the kitchen is well-vented.Keep th e following general ventilation rules in mindwhen choosing or modifying plans:It is best to have equal inlet and outlet areas.Ideally, about 12% of the floor area should havescreened openings. For second floors, 10% sade qua te. If this is all met by sliding or single- ordouble-h ung windows w here 55-60% of the win-dow is fixed, excessive wind ow area w ould berequired. T o keep glass area to a minimu m, use

screen front doors, atrium-style doors to screenedporches, and fully operable window types such ascasements and awnings to provide the requiredopenings.Openings on adjacent walls should be located asfar away from one another as possible.1Bedroom

Adjacent wall openings should be atopposite ends.Airflow is better with a screened balcony orporch than with window screens on the doors orwindows.

Window,creenson balconyVentilation is improved by having screenedporches or balconies instead ofwindow screens.


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Roof cupola

' art walllouvered at topRoof cupolas can aid ventilationregardless of wind direction.

Roof cupolas can aid ventilation, as can clerestorywindows (however, clerestory windows open dur-ing the day may bring in hot air off the roof).Low inlets are preferred for occupant c omfort.Therefore, screened doors and low windows arepreferred from a ventilation viewpoint.In two- or three-story structures, there will be aslight benefit from high outlets if air is permittedto flow from the first floor up to the higher levels.Mass will provide daytime cooling from nightventing. It is best to locate exposed (uncarp eted)floors and massive walls in living, dining and kit-chen areas, leaving bedrooms with less mass sothat they can be quickly cooled in the evening.For homes with massive walls or floors to store

Massive wall +

Massive floor

Locate openings close to massive wall or floor.

Ventilation+ attern, windfrom left+, ind fromClerestory windows can aid ventilation but maybring in hot air from the roofduring the day (wind from right).

the heat (or coolness), inlets should be positionedclose to the mass to create a wall or floor "jet."In rooms with one outside wall, two widelyspaced window s are better than o ne largewindow.Wingw alls (walls that protrude o ut from thehouse, next to the windo w) can be used toimprove ventilation. A wingwall should be aslong as the window is wide. It can increase air-flow, particularly in rooms with windo ws on onlyone wall. Appropriate uses of wingwalls areshow n on the next page. In some instances, thespace between the wingwalls can be used asindoo r or outdo or closet space. Casem ent win-dow s can act as wingwalls too (see Chapter 7).

Range of winddirections for which Perspectiveroom is effectivelyventilated

140"

Wingwalls direct air into the house.


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JOpenings on Openings onsame wal l adjacent wal l

#5a. Best

#6a. Best

#4. Poor

Ke y to symbolsShaded area indicates wind directions (from circumference to center)@ whereby airspeed would be increased.

Wingwall examples4-10


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12/23


10. Locate air handler andappliances properlyLook for designs which can contain the air handlerfor non-combustible furnaces, together w ith allductw ork, in the cond itioned space. This is a bigasset in reducing air infiltration and duct losses.Modify designs, if necessary, to put the air handlerwhere a coat closet or basement stairs are shown,and think of potential layouts for the ductwork inthe conditioned space.Washers, dryers and water heaters can be a sourceof heat and /or moisture to the house. Since aircond itioning is a greater conc ern than heating inFlorida, enlarge garages, carports, or closets off of aporch to provide non-conditioned space for theseappliances. Vent the dryer to the outdo ors.

11. Avoid fireplacesFireplaces are a source of air leakage, whether o rnot they are being used. It would be best to omitfireplaces from plans. If they are to be installed, seeChapter 11 for how best to install them.SummaryThe choice of hom e design can greatly affect theenergy use and com fort of the home own er. Properorientation, fewer window areas, and structuralshading can all help keep ou t some of the sun's heat.Glass should face north o r south unless facing aporch. Ove rhangs should be correctly sized forshading direct sun from south-facing glass andshould be used on all sides of the house. Sim plebuilding shapes are preferred but shading and venti-lation may dictate an irregular shape. All majorrooms should be cross-ventilated, and located wherethey will provide the most comfort to occupants.Choose plans which locate laundry appliances in thegarage and air handlers for non-combustiblefurnace s in the conditioned space. Consider theenergy disadvantages of a fireplace.


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House Plan Examples 8/0 1 90

D o not exp ect to readily find a hom e design thatincorporates all of this chapter's recommendationsand w orks well with the site you have selected. Sothat you can see how the preceding recommenda-tions can be carried through into the house design,this section includes examples of homes for sitesoriented to the north, south, east or west. If yoursite faces a different direction (northwest, for exam-ple), it would be best to orient the house so that thetwo sides with the m ost windows face within 1 5 O ofnorth or south. Tw o of the examples shown here,however, are site-independent- hat is, most glassis well shaded regardless of orientation. Also, thereare two multi-family examples, three zero-lot-linedetached h ome examples, and eight orientation-dependent detached home designs.Each example here is just that, an example; fullplans are not available. If you wou ld like to buildone of the exam ples, take the drawing to an archi-tect or residential designer. T o maintain the en ergyaspects of the design, do n ot alter window or o utsidewall locations.FSEC has other home designs available with fullconstruction drawings. The designs are winnersof state-wide competitions. Contact FS EC formore information.Most single-family home designs shown here have ascreened front door an d a two-car garage. In mostinstances, a on e-car garage or carport could be sub-stituted. (A carpo rt permits breezes to enter thehome and is preferred.)

Four-inch w alls are show n on most designs. Blockwalls could be substituted. All dimen sions arerounded to the nearest foot.Less com mo n abbreviations and sym bols usedin the examples are defined below:

Abbr./Symbol MeaningAHCLPR

WICWO-//////

Air handler for cooling1heating systemAir conditionercompressorLinen closetPantry closetRefrigeratorWalk-in closetWall ovenRoof overhang or

screened porch wallFence or railing

The plans are num bered with prefix abbreviationsfor quick identification. For example, SF isSouth-Facing.


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House Plan Examples

Orientation-independent plansHome plans that are adaptable to many lots regard-less of orientation should em phasize shading glassareas and avoid a disproportionate number ofunshaded windows on any one side. Example 01 -1is a plan similar to m any being built today, but withbetter shading provided. Front and back porchesstructurally shade most of the glass. A fewunshaded windows remain - ne in the front (mas-ter bath), two on one side (family room and secondbath), one on the other side (bedroom 2) an d one onthe back (bedroom 1)- ut overhangs and othershading devices (Chapte r 7) can help protect them.Ventilation of the main living areas, kitchen an dmaster bedroo m is possible. Bedroo ms 2 and 3require additional openings for ventilation when thedoors are closed.

------7-

SCREENEDPORCH

MASTERBEDROOM12x15

Example 01-2 is reminiscent of older Floridahomes, with a porch or veranda on all sides. High,narrow loft windows provide light and goodventilation.

- 40' -u i "7r-----'---'---'--'---'---- -------1SCREENED PORCH I8' i I

SCREENED PORCHI ILL -----a---L------ & --------

1744 SQ. FT .

1690 SQ. F T

Plan 01-1 Plan 01-2


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House Plan Ex am ~l es

North-facing single family hom e plansNorth-facing sites may be the best orien tation for anenergy-efficient, com fortable hom e. Examp le NF-1show s a two-story plan w ith thick block walls indi-cating space for exterior insulation. Note that theoverhanging second floor balcony shades the first-floor south-facing glass. There is no un shaded westglass. The Florida room should remain unconditi-oned and can serve as a screened porch in summer.North-facing glass is shaded from direct sun by theprojections. W alls create wingwall effects for venti-lation in bedrooms 2 an d 3. All rooms have goodventilation potential.

1290 SQ . FT.+'Q 240 50. KT . Florida roomPlan NF-1, 1s t floor

680 SQ . FT .

Plan NF-1. 2nd floor

Plan N F-2a is a simple, small rectangular plan witha hip roof an d tw o-car garage that will fit on mostlots. Shad ing on the west side is provided by thegarage and a screened porch. Tinted glass or analternate shading method should be used on thethree small east windows. Closets in bedroom s 2an d 3 act as wingwalls. Cross-ventilation potentialfor each room is good.

SCREENED 1PORCH17x14

Q 1275 SO . FT.N Plan NF-2a

Plan NF-2 b varies slightly from NF -2a. It adds wallarea but reduces shading problems for the east win-dow s, while m aintaining reasonable cross-ventilationpotential. A different interior layout is shown in thesouth-facing plan S F-2, which w ould also be effec-tive on no rth-facing lots.

i~~ 1275 S O . FTN Plan NF-2b


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House Plan Examples

South-facing single family home plans windows provide light, winter heat a nd ventilationto the m ain living area.Energy-efficient designs are easily adapted to south-facing home sites. A front overhang is recom- Plan SF-2 is the same as NF -2b excep t that an alter-mended w ith few or no side windows. Examp le nate room arrangeme nt is shown. There is directSF-1 show s east and w est windows, but they are access from the kitchen to the porch. The m irrorshaded by long overhangs on the west and a image of this plan would also be effective for south-screened porch o n the east. All rooms have good facing lots.ventilation potential. The south-facing clerestory

IIII1IIIIIL

1670 SQ. FT .

W&E 1275 SO. FT.s

Plan SF-2SOUTH ELEVATION

EAST ELEVATION

Plan SF-1


17/23

House Plan Examples

West-facing home plansAs previously discussed, the west is the worst sidefor glass. Choose designs which have on e or nofront windows, and which have a long porch on theback to shade the house from the m orning sun.Finding an energy-efficient west-facing plan is achallenge, but m any design options are available -although they m ay require modifications to a n exist-ing plan.

Keep house oriented on east-west axis. Putdesign emphasis on roof elevation and considerside-entry garages.Consider a house shape other than a simple rec-tangle to permit north- and south-facing glass andadequa te ventilation. Examples: a 7-shape,U-shape, H-shape.

Choose shapes with most windows on side.

Use a large, covered front porch to shade win-dows. Consider a Victorian or country design tomake the front porch a marketing feature.Plan W F -l a is a U-shaped plan that uses the garageand front porch to shade the house from the sun.The sh ape permits cross-ventilation for every room.If a longer front elevation is desired, a larger frontand back porch can provide the needed shade, asshown in plan WF-1b.Plan WF -2 has no front windows and will provideexcellent cross-ventilation to each room withsoutheast winds (a predominant wind direction inmany parts of the state).

1520 SQ. FT .L - - - - - - - - -J Plan WF-1 b

r - - - - - - - - - - - - 7SCREENED I

I PORCH 1

Plan WF-l a1360 SQ. FT

Plan WF-2


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East-facing home plansThe design criteria listed for west-facing plans willbe energy-efficient on east plans also. How ever,east-facing lots present the most difficult challenge inselecting com fortable and energy-efficient floorplans. Not only doe s the back of the house have tobe shad ed, but the ideal focal point of the propertyshould be shifted from the trad itional back yard to aside yard to avoid the afternoon heat. A C-shape(or reverse C-shape) house with most glass on itssides, but not in front or bac k, will create a pleasantoutdoor area, as shown in examples EF-1 and EF-2.Plan EF-1 succeeds in having no windows on theback of the house and an outdoor focal point on thesouth side. Due to th e projection of the master bathwing, occup ants can eat in the shade in the screenedarea d uring late afternoon and early evening insum mer. The so uth side is also the best location fora pool. Th e south glass will help heat the home inwinter. Every room except bedro om 3 has cross-ventilation potential, althoug h the garage may blocksoutheast breezes.

sGN460 50 . FT.E

Plan EF-2 maximizes cross-ventilation potential andthe use of south glass, for an energy-efficient plan.There is one front-facing east window and one small(4 square -foot) west window . The south-facing cle-restory windows provide light and winter heat forthe kitchen, living room, foyer and one bath. Anorth porch allows outdoor living/eating off the kit-chen and living room, and either the north or southside can serve as an outdoo r focal point. Tile floor-ing provides therm al mass for ventilation andpassive sola r heating.

* South facingclerestory2202 SQ. FT.sPlan EF-1 Plan EF-2


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House Plan Ex am ~le s

Zero lot line plansIn areas where land costs are high, many buildersuse high-density detached hou se zoning. A typicallot size is 50 by 100 foot. Usually one side of thehouse is built on the lot line and is without win-dows. Glass is provided on the oth er three sides.

Plan ZL-2 is better than ZL-1 if the lot faces northor south. The west side should always be the sidewithout windo ws. Cross-ventilation potential isavailable to all rooms except bedro om 2. East win-dows are shaded by the porch and patio.

Plan ZL-1 is best for east- or west-facing lots. Mo stof the glass is concentrated on the sou th side. Cross-ventilation potential is excellent. The op en-airatrium (screened roof) helps provide ventilation andlight to the kitchen and master bath, and thescreened porch and covered patio help shade otherglass. Yro'1STREET

Plan ZL-1 so

Plan ZL-1 site layout70-

- STREET

\ "170 SQ. FT.Plan ZL-2

Plan ZL-2 site layout

1100 SQ . FT. ' - - - -

Mirror image of ZL-1 Mirror image of ZL-2would be effective on would be effective onwest-facing lots. south-facing lots.


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Plan ZL -3 is for double-ze ro lot line sites. The re arewindows in the front part of one side and the backpart of the other side. Th e house is usually tilted onthe lot, creating a w ider elevation when viewed fromthe street. Since the garage has to occupy a fair por-tion of the front of the house, and the narrow widthalmost dictates that a porch go on the back of thehouse, east- or w est-facing sites are preferred. PlanZL-3 is an exam ple of such a case. A solid fence(shown in the site layout) m ay act like a partialwingwall and aid in cross-ventilating the diningroom and kitchen. A screened front door is essentialfor cross-ventilation of the living room .

Plan ZL-3

STREETPlan ZL-3 site layout

4-20


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House Plan E x a m ~ l e s

Multifamily plansMultifamily buildings frequently contain identicalunits side by side and , sometimes, abov e and below.In many multifamily buildings, windows are limitedto front and back. Du e to staircases, most units in amultistory, multifamily building have some shadingof front glass. A porch o n the back can provid efurther shading. North- o r south-facing sites arepreferred.Two-story units are best if situated side by side withopenings front and back - or cross-ventilation andso that all windows can be facing north or south.

47 'Plan MF-1 demonstrates an open floor plan thatpermits cross-ventilation of the kitchen /dining/liv-ing areas. A sitting area in the master bedroo m p ro-trudes to act as a wingwall for better cross-ventilation in that bedroom. Th e ventilationpotential of a multifamily building will depend onthe site, the spacing between buildings, an d the w aythe units are connected. Sh ow n is a metho d forconnecting the units to allow angled breezes to each.Additionally, each unit could have a view of a spe-cial feature of the site (river, lake, oc ean, golf course,etc.). Note that the washer and dryer are located onthe porch and the dryer can easily be vented to theoutdoors.

\V I E W

1200 SQ. FT.Plan MF-1Z+VIEW r - - - - - -

S N

Conn ect units so that breezes reach each one.


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8/0 1 90 House Plan Ex am ~ le s

Plan M F-2a is a two-story plan. Cross-ventilation ofthe second floor is possible by the opening from thefirst-floor dining room to the second-floor masterbedroom . Plan MF-2b shows an alternative cross-

ventilation design where the windows in the loft andmaster bath are at the opposite end of the masterbedroom windows.

1st Floor 1200 SQ . FT . 2nd Floor 600 SQ . FT.Plan MF-2a

1 s t Floor 1200 SQ . FT. 2nd Floor 6 0 0 SQ. FTPlan MF-2 b


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House Plan Examples

For further information"A Passive Solar Home Program for Florida," T.Way ne W aldron, Concrete Masonry Solar Architec-ture, Vol. 6, No. 3, August 1986."Guidelines for Energy-Efficient M ulti-FamilyHousing Design," Mike Nicklas, Concrete Maso nrySol ar Architecture, Vol. 6 , No . 3, August 198 6."Solar Hom es Design Portfolio," Tennessee ValleyAuthority (TVA), 1985.

"Passive S olar Design Co nsideration s for NorthCen tral Florida," F lorida R egion I11 Energy ActionCom mittee an d G ainesville Regional Utilities (alsoreprinted by Jacksonville Electric Authority).Coo ling with Ventilation, Sub rato Cha ndra, PhilipW . Fairey 111, Michael M. Houston, Solar EnergyResearch Institute - Sp-273-2966, Golden,Colorado, 1986.Climate Design, Donald Watson, K enneth Labs,McG raw-Hill, Inc., New Yo rk, 1983.

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