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RADIANT FLOOR HEATING INSTALLATION TECHNIQUESTIME-SAVING TECHNIQUES FOR LASTING RESULTS

© REHAU 17-Mar-10-

RAUPEX PIPE AND MANIFOLD INSTALLATION

- “Wet” installation methods- Pipe placement patterns- “Dry” installation methods- Manifold locations- Sleeving of pipes- Step-by-step installation process- Avoiding difficulties

OUTLINE

© REHAU 17-Mar-10-

POURED OR “WET” CONSTRUCTION

- Slab or overpour applications - Thermal mass is poured into

place around RAUPEX pipe- Structural concrete mix

(fibers may be used)- “Lightweight” concrete: sand

mix, dry pack (not aerated)- Gyp-Crete, Hacker floor

systems

TYPES

© REHAU 17-Mar-10-


- Pipes to be fastened every 2 feet (typical) or as needed to prevent “floating”- For medium thick slabs (4”) pipes may be installed at the bottom or in the middle- For thick slabs (6” and above), pipes are normally installed in mid-point, unless there is a

risk of cutting/drilling the pipes- Then move them lower in the slab to avoid damage- Coverage over pipe must be minimum 3/4” for concrete strength and to avoid striping

- Entrained air in concrete is bad for heat transfer - Avoid concrete with entrained air

- Wet thermal mass has lots of moisture which needs to evaporate- Must let it dry before hardwood flooring is installed

- Floor loading of poured thermal mass is critical (13-18 lb/ft2 dead load for 1 1/2” overpour)- Depending on the mix; 2,000 ft2 = 30,000 lbs- Floor must be designed to carry this load

- Coordination of trades is important- Insulation, wire mesh, double baseplates, “dams” around holes, etc. all must be done

in the proper order

GENERAL RULES

© REHAU 17-Mar-10-


- Normal slab design- Pipe located within slab (midway) or at bottom- Various fasteners available- Typical layers:

Slab with RAUPEXRigid insulationVapor barrierCrushed stone

SLAB CUTAWAY, TYPICAL

1 1

22

3

34

4

© REHAU 17-Mar-10-

SLAB-ON-GRADE “WET”

Why so important?- For even heat transfer towards space, floor temperatures- To minimize heat loss to earth (below, backfill) and air (at edges)- To decrease response time and increase efficiency

General Rule*:- R-value below the slab should be at least 5 times R-value above the slab

IMPORTANCE OF INSULATION

*Note: 2” insulation (R-10) is recommended at slab edges and below slabs on earthSuspended slabs (over cold air) will require even more insulation

Example: Commercial carpet with pad installed above slab, total R value = 1.5Use minimum R-7.5 insulation below (1 1/2” of extruded polystryene) and 2” at cold edges

© REHAU 17-Mar-10-

SLAB-ON-GRADE “WET”TYPICAL CONSTRUCTION LAYERS FOR HEATED SLAB FLOORS

Vapor Barrier

Thermal Mass with pipes

Edge

*In

sula

tion

*Note: 2” insulation (R-10 for EPS) is recommended at slab edges and below slabsSuspended slabs (over unconditioned cold air) will require even more insulation

Heated Space

Sub-Grade

Bottom* Insulation

© REHAU 17-Mar-10-

SLAB-ON-GRADE “WET” WITH RAILFIX

EXAMPLE: STYROFOAM® SM BOARDSTHESE GO DIRECTLY ONTO EPS INSULATION

© REHAU 17-Mar-10-

SLAB-ON-GRADE “WET” WITH SCREW CLIPS AND RAILFIX

RAILFIX

Screw Clip

THESE GO DIRECTLY ONTO EPS INSULATION

© REHAU 17-Mar-10-

SLAB-ON-GRADE “WET” WITH FIXING RAIL OR RAUTACKERTHESE GO DIRECTLY ONTO EPS INSULATION

RAUTACKERRAUTACKER staple

© REHAU 17-Mar-10-

SLAB-ON-GRADE “WET” WITH NYLON TIESREHAU NYLON PIPE TIES TIED TO WIRE MESH

- REHAU nylon pipe ties - 50 lb. capacity, installed every 2 – 3 feet maximum- Ensure wire mesh has no sharp edges

© REHAU 17-Mar-10- Page 18

SUSPENDED WOOD FLOOR “OVERPOUR”

- Pipe is fastened to subfloor- 1 1/2” total height (typical)- Minimum coverage must be 3/4”

above pipes- To avoid heat striping and

weak concrete- Thin thermal mass overpour may

be gypsum cement concrete or portland cement concrete with small aggregate (3/8” or smaller)

ALSO A “WET” INSTALLATION

- Ensure that subfloor is designed for the “dead weight” of 13-18 lb/ft2

- Clarify definition of “lightweight”- Concrete is never light!

1 1/2” totalMinimum 3/4”above pipes



- Very common installation technique- Freedom to lay pipe according to room design- Use proper stapler tools to avoid crimping or

dimpling pipe- REHAU Pneumatic Stapler by SENCO

GENERAL NOTES



- Can also use pipe talons

GENERAL NOTES



Heated space below:- R-value in the joist cavity below a heated

overpour should be at least 5 times R-value above (flooring + floor)

Examples:- Tile above, Minimum R-5 in joist cavity- Carpet above, Minimum R-11 in joist cavity

Unheated space below:- R-value in the joist cavity below a heated

overpour should be at least 10 times R-value above (flooring + floor)

Examples:- Tile above, Minimum R-13 in joist cavity- Carpet above, Minimum R-19 in joist cavity

IMPORTANCE OF INSULATION

- Heat goes to cold and will go down without proper direction

- Insulation in the joist cavity is crucial to comfort, performance and response



- Install all baseplates to mark walls before laying pipe

- Assists routing pipes- May have to install

loadbearing walls at the same time

- Use double baseplates:- Extra-wide baseplates on the

bottom, standard size on top- 2” x 8” bottom plate at

outside walls- 2” x 6” bottom plate at inside

walls- For leveling screed- For carpet tack strips

TIPS



- Double baseplates, extra wide (that was not done here)

- Recommend:- 8” wide under 2” x 6” wall- 6” wide under 2” x 4” wall

- Install baseplates to mark walls before laying pipe

- May use pressure-treated lumber, but not necessary

TIPS



- Common with solid hardwood- Benefits of thermal mass- Freedom to lay pipe according to

room design- Install sleepers opposite to

orientation of hardwood- Use caution due to moisture!

- Thermal mass must cure and moisture must be correct before hardwood is installed

- May take 28+ days for curing- Work with flooring contractors

and GC for proper scheduling

“SLEEPERS” FOR HARDWOOD INSTALLATIONS


SUSPENDED WOOD FLOOR “OVERPOUR”BE SURE TO SEAL OR COVER THE SUBFLOOR FIRST WHEN USING A PORTLAND CEMENT CONCRETE OVERPOUR TO PREVENT BONDING AND SHRINKAGE OF THE CONCRETE


SUSPENDED WOOD FLOOR “OVERPOUR”GYPSUM CEMENT POURS DIRECTLY ONTO WOOD SUBFLOOR (PUMPED)FLOOR IS USUALLY SEALED FIRST



- Poured thermal mass is a good conductor of heat- Pipes to be fastened every 2 feet (typical) or as needed to prevent “floating”- For medium thick slabs (4”) pipes may be installed at the bottom or in the middle- For thick slabs (6” and above), pipes are normally installed in mid-point, unless there is a

risk of cutting/drilling the pipes- Coverage over pipe must be minimum 3/4” for concrete strength and to avoid striping- Entrained air in concrete is bad for heat transfer - Insulation is crucial to direct the flow of the heat- Wet thermal mass has lots of moisture which needs to evaporate

- Must let it dry before hardwood flooring is installed- Floor loading of poured thermal mass is critical (13-18 lb/ft2 dead load for 1 1/2” overpour)

- Depending on the mix; 2,000 ft2 = 30,000 lbs- Coordination of trades is important

- Insulation, wire mesh, double baseplates, “dams” around holes, etc. all must be done in the proper order

SUMMARY


PIPE PLACEMENT PATTERNS

1. Serpentine (overpour, slab, joist, sleepers)2. Counterflow Spiral (overpour, slab)

- Helps with bends- Faster installation in the right situation- More even temperature distribution

3. Combinations (overpour, slab)4. Other shapes

THREE TYPES OF PIPE LAYOUTS


1. SERPENTINE

- Install pipe the “long way” to minimize bends, for faster installation

- Great for rectangular rooms

- Great if there is one outside “cold” wall

- Run hottest water to outside wall

- Floor covering (hardwood) way also dictate the direction

13 x 180-degree bends4 x 180-degree bends


SERPENTINE

Straight or in L-shape

SIMPLE LAYOUT, EASY INSTALLATION


SERPENTINEDOUBLE 180- BEND REDUCES SHARP BENDS


SERPENTINE‘U’–SHAPE IN SOME AREAS


SERPENTINEL-SHAPED SERPENTINE


2. COUNTERFLOW SPIRALEVEN FLOOR TEMPERATURE, REDUCES NUMBER OF TIGHT BENDS, FASTER INSTALLATIONBEST PATTERN IF THERE IS NO OUTSIDE WALL, OR ALL OUTSIDE WALLS


COUNTERFLOW SPIRALEVEN FLOOR TEMPERATURE, REDUCES NUMBER OF TIGHT BENDS, FASTER INSTALLATIONBEST PATTERN IN LARGE OPEN AREAS


COUNTERFLOW SPIRALUSE STAPLES OR TALONS


3. COMBINATIONCORNER ROOMS

OccupiedArea

Supply

Return

PerimeterArea (3 ft.)

OutsideWall


4. OTHER SHAPES…IN BATHROOMS USE MORE PIPE, NOT LESS. TRY 3/8” RAUPEX FOR FLEXIBILITY


4. OTHER SHAPES…IT IS IMPORTANT TO FILL THE HEATED SPACE WITH PIPES AND AVOID GAPS (COLD SPOTS)


CONSTRUCTION JOINTSARRANGE PIPES TO AVOID PASSING THROUGH JOINTS


JOIST SPACE “DRY” INSTALLATIONS

- No poured screed is involved (“dry”)- Aluminum plates, the air cavity (in joist space) and the subfloor are all parts of the

thermal mass- Aluminum heat transfer plates are very important for efficiency and response

- Can increase efficiency by 20% to 40%

GENERAL RULES FOR JOIST SPACE INSTALLATIONS



Pro’s:- Suitable for retrofit- No structural weight issues- No added moisture

Con’s:- Installation can be difficult and slow- Not the most efficient radiant technique

- Higher water temperatures will be required, as compared with other RFH

- Slower response time compared with pipes installed above the subfloor

- High R-value insulation is critical underneath plates and at ends of cavities

- Below the 2” air gap: - Minimum R-19 over heated space- Minimum R-30 over unheated space

GENERAL RULES FOR JOIST SPACE INSTALLATIONS

Typical 2” x 10” joist construction with 2” air gap.Follow the path of the heat

How does it work?



Light Gauge Heat Transfer Plate

Locking Clip Talon

MAINTAIN 2” AIR GAP BELOW SUBFLOOR FOR FULL HEAT TRANSFER, REDUCED STRIPING



- Uncoiler is very useful in larger areas- Otherwise, 2-3 workers is ideal

- With light gauge plates, install all pipe, then plates

- With heavy gauge plates, install the plates first, then snap in the pipes

- Use protection sleeving at joist penetrations to prevent chafing and possible noise of rapid thermal expansion

- If the design allows, 3/8” RAUPEX O2

Barrier pipe is more flexible than 1/2”pipe, faster to install

- Feel free to use EVERLOC couplings when in a jam Pipe must be

free to move at ends

PE Protection Sleeve

INSTALLATION TIPS



- Heat transfer plates enhance heat distribution- 20 - 40% improvement

- Use 6 screws per light gauge plates- Use 8 screws per heavy gauge plates

- Because staples may work loose over time, and plates would fall down

- Insulation is important (foil face up for radiation)

- Insulation should be 2” away from subfloor (for convection heat transfer)

- Be careful of sharp edges on heat transfer plates. Wear eye and hearing protection when cutting heavy gauge plates. Wear work gloves.

MAINTAIN 2” AIR GAP BELOW SUBFLOOR FOR FULL HEAT TRANSFER, REDUCED STRIPING


JOIST SPACE “DRY” INSTALLATIONSLIGHT GAUGE PLATES – 2 FEET LONG EACH


JOIST SPACE “DRY” INSTALLATIONSHEAVY GAUGE PLATES – 4 FEET LONG EACH


JOIST SPACE OUTPUT – FINITE ELEMENT ANALYSISSAMPLE CALCULATION WITH HEAT TRANSFER PLATESTHEORETICAL JOIST-SPACE SYSTEM WITH R-1.0 FLOOR COVERING

- FEA shows that heat is conducted by Heat Transfer Plates and is distributed more evenly under the entire subfloor and joist cavity

- Lower water temperature, more efficiency, better response time


JOIST SPACE OUTPUT – FINITE ELEMENT ANALYSIS

- FEA shows that heat is concentrated in the air around the pipes- There is less transfer to subfloor, more striping on floor surface

- Higher water temperature, less efficiency, slower response time

SAMPLE CALCULATION WITHOUT HEAT TRANSFER PLATESTHEORETICAL JOIST-SPACE SYSTEM WITH R-1.0 FLOOR COVERING



- Installation can be difficult and slow depending on obstructions, ceiling height, etc.- Zoning is very difficult since pipes must follow joist bays under several rooms- Perimeter spacing is the same as occupied spacing (determined by joist spacing)

- Usually 8” o-c, sometimes 7”, 9” or 10”- Aluminum heat transfer plates are very important for efficiency and response- High R-value insulation is critical underneath plates and at ends of cavities- Higher water temperatures will be required as compared with above-floor installations- Slower response time compared with pipes installed above the subfloor- Outdoor reset control with continuous circulation is recommended, especially with light

gauge plates, to help avoid expansion noises and to improve response times

SUMMARY


MANIFOLD LOCATIONS

- Install in the back of a closet, or cabinet- Leave enough room for all pipes to connect- Mount manifold 30-40” above floor in an

accessible location- Position manifold in its “final resting place”

so that pipes are routed correctly- Ex: Build a support along framed walls

MOUNTING


MANIFOLD LOCATIONS

- Install in the back of a closet, or cabinet- Leave enough room for all pipes to connect- Mount manifold 30-40” above floor in an accessible location- Position manifold in its “final resting place” so that pipes are routed correctly- Ex: On new slabs, make a support with rebar or wood studs

MOUNTING


MANIFOLD LOCATIONS

- Place in permanent position- Mount 2 - 4 feet above grade- Mount level and secure

- May have to create supports- Leave room for pipe access

- Note pipes passing under wall

ROUTING PIPES


MANIFOLD LOCATIONS

- Find an opening the correct size- Refer to the dimensional drawing

in the installation brochure- Try to align the pipes!

PLANNING THE LOCATIONS

Not a great example here!


MANIFOLD LOCATIONSPLANNING THE LOCATIONS THROUGHOUT THE BUILDINGEXAMPLE: OPEN AREA, 2 MANIFOLDS FOR 10 CIRCUITS


MANIFOLD LOCATIONSPLANNING THE LOCATIONS THROUGHOUT THE BUILDINGEXAMPLE: OPEN AREA, 1 MANIFOLD FOR 10 CIRCUITS

#3

#4

#2

#5

#1

#10 #9 #8 #7

#6


PVC BEND GUIDE INSTALLATION

- Insert pipe into PVC Bend Guide - Use 30” - 40” of pipe to reach

manifold- Adjust all bend guides to same

height and even spacing- These will be partially encased

in concrete and will be visible

STEP TWO


PVC BEND GUIDE INSTALLATION

- PVC Bend Guides look great when complete- They protect and align the pipe and take

stress off pipe connections

STEP TWO


INSTALL RAUPEX PIPE

- Bending radius of 5 times the pipe OD without heat; the tightest of all PEX pipes- Bending radius of 3 times the pipe OD when heated; the tightest of all PEX pipes

- Pipes are less likely to kink when bending slowly

21.2510.6252.1252"16.258.1251.6251 1/2"13.756.8751.3751 1/4"11.255.6251.1251"8.754.3750.8753/4"7.503.7500.7505/8"6.253.1250.6251/2"5.002.5000.5003/8"

5x MinimumBend

Diameter in.

5x MinimumBend

Radius in.

Pipe OD (actual) in.

Pipe Size(nominal)

Radius (r) Diameter (2 x r)

r d

STEP FOURTIPS FOR INSTALLING RAUPEX PIPES


INSTALL RAUPEX PIPE

- Minimum bend radius for RAUPEX pipe is 5 times the pipe diameter when cold

- Bend slowly, especially in cold weather

- Minimum bend radius is 3 times the OD when pipes are heated above 250°F

- Use hot air gun (ONLY) - Heat pipes only without pressure

- Fasten pipe at the beginning, middle and end of each bend to prevent “lifting”

- If pipe tends to lift, add extra fastener(s)

See Page 5-5 REHAU RFH Technical Manual



INSTALL RAUPEX PIPE

- Attach pipe every 2 - 3 feet using approved fasteners- Ensure pipe is straight and doesn’t “lift”- If pipe seems to float, add more fasteners

- Mark circuit lengths and locations as you go- Insulate pipe tails if necessary

- But don’t weaken the concrete- Don’t cross pipes in “poured” applications

- Don’t weaken the concrete


Saw cut is very close to top of pipes. Add fasteners!


INSTALL RAUPEX PIPE

- Install sleeves at penetrations- Install sleeves at expansion joints- Joist space sleeving prevents noise

STEP FOURPROTECTION SLEEVING


INSTALL RAUPEX PIPE

- Start installing pipes on outside walls so that hottest water (from Supply) goes to perimeter areas first

- Keep pipes 6” away from walls, holes, cabinet mounting points, and toilet gaskets

- To reduce heat transfer- For protection of pipes- To prevent softening



AIR PRESSURE TEST

- Pressurize pipes and manifold(s) together through the manifold

- Normal test pressure is 1 1/2 times working pressure or 100 psi (whichever is higher)

- Re-pressurize at 10 and 20 minutes to allow for expansion of pipes

- Keep constant temperature- Maintain test pressure for 2 hours

- Note: Air tests are safe up to a maximum of 200 psi as long as pipes are used with brass manifolds, EVERLOC fittings, and no plastic components

STEP FIVE (OPTION A)AIR TESTS ARE ALLOWED BY REHAU AND ARE RECOMMENDED IN FREEZING CONDITIONS

REHAU Air Tester Art. 257334


WHAT NOT TO DO

- Don’t hang manifold crooked or remove from brackets

- Don’t install without brackets - Don’t leave pipe in the sunlight - Don’t cut pipe with a hacksaw or

pocketknife- Don’t let pipe float close to surface- Don’t leave excessive gaps between

pipes to result in cold spots- Don’t forget to clip or move nylon ties

Improper manifold mounting

DON’T LET YOUR JOBS LOOK LIKE THIS!


WHAT NOT TO DO

- Don’t forget PVC bend guides at manifolds

- Try to line them up!

Improper pipe positioning



WHAT NOT TO DO

- Don’t mix up Supply and Return- Don’t lose track of pipes- Don’t hang manifold crooked or

remove from brackets- Don’t install without brackets

- Don’t cut pipe with a hacksaw or pocketknife

- Don’t let pipe float close to surface- Don’t leave excessive gaps between

pipes to result in cold spots- Don’t forget to clip or move nylon ties

Improper manifold mounting


radiant floor heating installation … floor heating installation techniques time-saving techniques...

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