CONVERSION ASSESSMENT

FOR THE

PROPOSED BARN CONVERSIONS

AT HOLDEN GREEN FARM

HOLDEN

BOLTON BY BOWLAND

CLITHEROE

FOR DR TATTERSALL

Date: 3 March 2020 Our Job Ref : 5978 Author: Lynne Rushworth

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1. Introduction

1.1 This assessment has been prepared to support the planning

application by the applicant, Dr Tattersall; to convert a 19th century

traditional stone built barn and a 20th century stone built barn to

provide two holiday cottages and extend the farmhouse into the

attached barn.

1.2 It is proposed to convert Barn 1 into a 2 bedroom holiday cottage,

and partial conversion to extend the existing farmhouse living

accommodation. The Shippon is to be converted into a 1 bed holiday

cottage.

1.3 The barns were inspected on 3rd March 2020

1.4 At the time of the inspection the weather was sunny and

approximately 7ºC.

1.5 The assessment was limited to a visual inspection, no exposure work

was undertaken.

1.6 The site address is Holden Green Farm, Holden, BB7 4PG. OS Grid

Reference SD 772494 elevation 118m.

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2. Condition Assessment Barn 1

Photograph (1) – The current condition of the barn roofs.

Roof Structure

2.1 The roof over barn 1 is covered with grey slates which are laid to

diminishing courses. The roof is in poor condition with numerous

slipped, delaminating and cracked slates. The lead detailing at

abutment with the wall is poor, in some areas lead flashings are

missing where they would usually be present, water is likely to be

entering the structure at these points, but no major breaches were

noted. There are significant undulations particularly over the cart

opening.

2.2 The barn has a traditional timber roof construction consisting of

trusses, purlins and rafters with a slate finish. There is no felt present

in the roof build up.

2.3 Rainwater goods were present to the majority of the roof slopes over

barn 1.

2.4 The timber roof structure could only be inspected from ground floor

level. The main roof timbers ( trusses & purlins) that were visible on the

whole appeared in reasonable condition. The timbers appeared dry

but, including at the ends where they are built into the solid masonry

walls and there was some evidence to suggest the timbers had been

attacked by wood-boring insects. A significant number of battens are

broken over the cart opening and throughout the rest of the roof.

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Photograph (2) Roof structure to barn 1.

Photograph (3) – Roof structure over the west cart opening of barn 1.

2.5 There were numerous areas where the roof timbers (battens and

rafters) were in poor condition, these roof timbers will need

renewing throughout as part of the conversion works.

2.6 The trusses and purlins are in average condition there are some

signs of wood boring insect activity in both trusses, the right hand

truss being affected quite significantly see photograph (4)

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Photograph (4)- right hand truss

The bottom tie member should be replaced and both trusses to be

treated for insect infestation.

2.7 The purlins can be retained but water ingress at the abutment of the

shippon wall and barn catslide section of roof may have affected the

purlin end, if during the work rot is evident replace purlin.

Cat slide roof (5)

Purlins over cart opening (6)

2.8 The timber head over the cart door opening is cracked and will be

replaced with a hardwood timber head. See below.

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Cart opening head to be replaced (7)

2.8 During the conversion works a closer inspection will be undertaken of the

roof timbers and if wood-boring insects are found this will be treated

during the works. If rot is found in the purlin ends over the cat slide they

will be replaced. A significant number of roof timbers will have to be

replaced during the conversion. The roof slates will be stripped during the

works to enable a new breathable roofing membrane to be fitted

throughout, the existing slates which can be reused will then be re-fixed

and supplemented with matching reclaimed grey slates over new timber

battens. 3no conservation roof windows will be incorporated without

compromising the original roof structure.

2.9 Rainwater goods were present to the main roof, however they were in

poor condition and will need renewing as part of the conversion works.

Walls

Photograph (8) Illustrating the condition of the rear (east) wall to barn 1.

2.9 The barn walls are of traditional solid masonry construction. Walls

of this type were traditionally built up in two leaves with rubble fill in

the cavity between.

2.10 The majority of the walls were in reasonable condition given the

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barns age. The majority of walls were straight and true however

some isolated cracks requiring remedial works are noted below.

None of the walls will be demolished during the conversion

works, however all walls will need re-pointing.

East Elevation

2.11 The East elevation the stone in reasonable condition as shown

in photograph below. However, a few repairs are required as set

out below. Some mortar removal is required in some areas to

reveal the stone, however the walls will be re-pointed during the

conversion works.

2.12 The timber head over the door opening shown below is severely

weathered and will need to be replaced with a stone head.

Head to be replaced (9)

West elevation

Photograph (10) Illustrating the condition of the front (west) wall to barn1

2.13 The walls are straight and true with no significant cracks. The existing

pointing will be raked out prior to repointing. Stone heads in good

condition and can be retained.

Walls Internally

2.13 Internally the walls were in good condition overall, the stone walls

were finished with lime wash some areas with a paint finish. In

some isolated areas water was entering the structure via the roof.

The walls were straight and true throughout with just a couple of

isolated minor cracks. all walls were of solid stone construction.

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There is however a section of wall adjacent to the shippon which

has failed.

(11)

The crack illustrated is located on the left hand return wall of the cart

opening stitching in is required.

(12)

The rear right hand corner rear elevation wall minor crack requiring

stitching.

Photograph (13 and 14) – Illustrating the condition of the internal walls.

Floors

2.14 The existing ground floors to the barn is compacted earth,

however these will need to be removed to enable the installation

of a concrete floor complete with thermal measures and moisture

resistance to meet the requirements of the building regulations.

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2.15 There is a floor over a store this structure will be will be removed

to enable a new first floor to be installed.

2.16 The new timber first floor will be supported by the new

blockwork lining walls.

2.17 Externally the ground levels will remain largely unaltered to

ensure adequate cover over the existing foundations to the walls

is maintained.

3. Condition Assessment Shippon Roof Structure

Shippon roof structure condition (15)

3.1 The roof of the Shippon is finished with grey slates which are

supported by timber battens, purlins, rafters and trusses. There is

timber boarding internally to the underside of rafters. The structure is

mono/ lean to pitch.

3.2 The roof is in reasonable condition. The roof has been underdrawn with

timber internally, sections are missing as can be seen below. It is likely

these have got damp over time and failed.

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Roof condition internally (16)

3.3 The timber trusses and purlins are in good condition and can be retained.

The roof slates will be stripped during the works to enable a new

breathable roofing membrane to be fitted throughout, the existing slates

which can be reused will then be re-fixed and supplemented with

matching reclaimed grey slates over new timber battens and purlins.

Photograph (17 - 18) – Trusses and purlins in Shippon

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Walls

Condition of the West elevation of Shippon (19)

3.4 The walls of Shippon were constructed from solid stone, walls of this

type were traditionally built up in two leaves with rubble fill in the cavity

between.

3.5 The front (west) and part rear (east) walls are in poor condition near to

the dividing (party) wall between the shippon and barn which was built

up off the main barn existing walls to form the lean to/ mono roof. The

wall which projects above the pitch barn roof has moved affecting both

front and rear elevations at the corners.

West Elevation

Photograph (20) – Illustrating the condition of the wall.

3.6 The failure of the party wall has caused movement in the front elevation

necessitating the need to partially rebuild re using existing stone.

The stone head of the window will need replacing to match existing.

The pointing is poor on the whole elevation and during the conversion

works this wall will be repointed.

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Photograph showing the areas of wall needing rebuilding (21)

Stones outlined in yellow require stitching (22)

East Elevation

3.7 This wall appeared in average condition nearest to the north corner,

however towards the south elevation the condition was poor. The section of

south elevation wall is bulging and is pulling away from the east elevation

wall. A bow in the east wall has been tied. Section of wall to be rebuilt.

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Photograph (21) – General wall condition to the Shippon south elevation.

3.9 This wall should be rebuilt. Reusing existing stone

North Elevation

Photograph (22) – General wall condition to this elevation

3.10 The wall is in reasonable condition and is straight and true, the pointing

is in poor condition and will be hacked off and the walls repointed

during the conversion works. All stone surrounds are in good condition

and will be retained.

Walls Internally

3.11 Internally the walls were finished with a mixture of painted render or

lime wash, they were generally in good condition with the exception of the

sections of the party wall between barn/ shippon which were built up above

the main barn roof, and the return wall ( south elevation).

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The partially collapsed internal wall (as shown below), will be removed during

the course of the works and rebuilt.

Photograph (23) – Showing collapsed section of wall to be rebuilt

Section of return wall (south elevation) to be rebuilt and tied into

existing main barn wall.

Photograph (24) Showing section of return wall ( south elevation) to be rebuilt

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Floors

3.12 The existing ground floors to the barn are concrete, however these will

need to be removed to enable the thermal and moisture resistance of

the floors to be improved to meet the requirements of the building

regulations.

Photograph (25) – Illustrating the condition of the concrete ground floor.

3.13 There is no first floor present.

3.14 Externally the ground levels will remain largely unaltered to ensure

adequate cover over the existing foundations to the walls is

maintained.

Conclusion

The barn is in sound condition and is suitable for conversion without major

intervention. The Shippon has some sections of wall which require rebuilding

to stabilize the building to prevent future collapse.

The walls, roof and floors will all need to be upgraded to meet the current

building regulations but this can be done with minimal impact on the existing

structure, meaning that the barns are suitable for conversion,