Barn conversion to holiday let in Slough | Case Study

The brief

Kennet & Avon Homes took on a redundant timber-framed barn on the eastern edge of Slough, where the built-up area gives way to paddocks and smallholdings. The barn had once formed part of a larger farmstead and still had the long, low proportions typical of agricultural buildings in the Thames Valley. The client's plan was to convert it into a holiday let aimed at visitors working in London who wanted a countryside escape within reach of the M4 and Crossrail. The target completion date was mid-October, in time for the autumn short-break market.

The building was not listed, but it sat within a conservation area that required external materials to respect the local vernacular. The planners wanted the brick plinth repaired rather than rebuilt, the roof profile retained, and any new windows set back behind the original frame line. We attended the pre-application meeting with Kennet & Avon Homes and the architect to understand these constraints before pricing the structural pack.

The design kept the timber frame exposed internally, formed new internal rooms using lightweight stud partitions, and wrapped the exterior with a new cavity wall built just outside the frame. A new insulated ground-floor slab would replace the existing concrete and earth floor, and the roof would be stripped, re-decked and re-tiled. Because the barn was long and narrow, the quantity of bricks required was large relative to the floor area.

We priced the full structural schedule from the drawings and agreed a fourteen-week delivery plan. The brick order was the largest single line item at 12,326 bricks, so we placed it early and held the material at our yard in staged releases. The client also wanted a higher-than-standard quantity of hardwood plywood for internal joinery, which was reflected in the fourteen sheets specified.

• Client: Kennet & Avon Homes
• Location: Slough, Berkshire (SL1, SL2)
• Project: Barn conversion to holiday let
• Duration: 14 weeks
• Star Hawk material cost: £17,350

The challenge

The most pressing challenge was the scale of the brickwork. The barn was roughly twenty metres long with a plinth that needed rebuilding in places and new cavity walls running the full length on both sides. That volume of brickwork, 12,326 bricks in total, had to be delivered in manageable loads because there was no space to store more than a few days' worth of bricks on the narrow site. We agreed to release the bricks in six separate drops, each timed to the bricklayer's output.

The second challenge was the location on the edge of Slough. Although the site felt rural, it was close to residential streets and the access lane was used by dog walkers and horse riders. Deliveries had to avoid school-run times, and loose materials had to be contained so that they did not spread onto the lane. We used a 7.5-tonne tipper for aggregates and a flatbed for bricks, blocks and sheets, with a sheeted load for any dusty materials.

The third challenge was the hardwood plywood requirement. Fourteen sheets of premium hardwood plywood were specified for window boards, built-in shelving, a small kitchen island carcase and bathroom boxing. Because these sheets were to be finished with lacquer rather than paint, the faces had to be unmarked. We inspected each sheet at the yard and separated any with surface damage for use in hidden areas rather than visible faces.

The summer start helped with some aspects but brought others. Long dry days were good for bricklaying and roof work, but they also meant that dust from the site was more likely to affect neighbours. We made sure that aggregate drops were damped down and that the tipper did not carry loose material on the road.

Finally, the holiday-letting use meant that sound insulation and fire separation were critical. The internal stud partitions had to achieve specific acoustic ratings, and the walls between the sleeping areas and the living space needed to meet fire-resistance requirements. Although the plasterboard and insulation finishes were supplied by others, our structural timber and fixings had to be compatible with those specifications.

Materials we supplied

Kennet & Avon Homes sent us the specification and we priced the full structural pack in one quote, then staged it across the fourteen-week programme. The exact quantities supplied to the Slough site were:

• Foundations and sub-base: 6 tonnes of MOT Type 1 Aggregate, 197 bags of General Purpose Cement, 19 tonnes of Building Sand, 15 tonnes of 20mm Ballast Aggregate.
• Walls and masonry: 1767 blocks of Aircrete Blocks, 12326 bricks of Hampton Rural Blend Brick.
• Openings: 4 lintels of Standard 100mm Cavity Lintel fitted across the three windows and the single doorway.
• Timber and sheet materials: 1.6 cubic m of C24 Timber, 228 linear m of BS Treated Battens, 38 sheets of OSB3 Board 18mm, 14 sheets of Premium Hardwood Plywood, 16 sheets of PIR Insulation Board.
• Insulation: 38 sheets of Cavity Insulation Slab.
• Fixings and hardware: 14 boxes of Galvanized Nails, 8 boxes of High Performance Wood Screws.

The 1,767 Aircrete blocks formed the inner leaves of the long cavity walls and the load-bearing elements of the internal partitions. The 12,326 Hampton Rural Blend bricks were the dominant material on the project, used for the outer leaf visible through the frame, the plinth repair and the small piers that supported the new porch. We released these in six drops of roughly 2,000 bricks each.

Only four cavity lintels were needed because the openings were limited to three windows and one set of doors, all of modest span. The 1.6 cubic metres of C24 timber were used for wall plate repairs, internal studwork and temporary bracing during the frame repair. The 228 metres of treated battens went on the roof as counter-battens and tiling battens.

The thirty-eight OSB3 boards formed the new roof deck and some internal infill panels, while the fourteen hardwood plywood sheets were reserved for visible joinery. The sixteen PIR boards insulated the roof, and the thirty-eight cavity insulation slabs filled the walls. We kept the hardwood plywood under cover at our yard until the joinery phase to protect the faces from marking.

Before each load left our yard, we checked the quantities against the drawings and the build programme. A delivery of bricks that arrived with inconsistent colouring was separated and returned to the manufacturer before any of it reached the Slough site.

Delivery and logistics

The Slough deliveries were planned around the bricklayer's progress because the brickwork was the longest single activity. The first drop was the sub-base and concrete materials for the new floor slab: six tonnes of MOT Type 1, the ballast and the bulk of the cement. Because the existing floor was partly concrete, the excavation was shallower than on many barn conversions, which is why the MOT quantity was relatively modest.

Bricks began arriving in week three, after the sample panel had been approved by the conservation officer. Each drop contained approximately 2,000 bricks, enough for four or five days' work, and was placed on the site using the flatbed's tail lift where possible or offloaded by the builder's telehandler. The blocks for the inner leaf arrived alongside the bricks in the same drops.

The timber, battens, OSB and PIR were delivered in week eight, once the walls were up to wall-plate level and the roof was ready to be stripped. We sent a flatbed with a Hiab that could lift the materials over the new wall and place them inside the barn. The hardwood plywood was delivered separately in week ten to avoid it being used prematurely or damaged during the roof phase.

Fixings and smaller items were added to the masonry drops or sent by van. We also kept a reserve of cement and sand at the yard against the builder's account. That reserve was used on three occasions during the programme, each time delivered within a few hours of the request.

The site manager texted our trade counter each evening with a progress update and any changes for the following day. That routine allowed us to adjust drop times to avoid the morning and afternoon school-run traffic on the nearby road, keeping neighbours and pedestrians happy.

The build

The fourteen-week programme began in late June with the removal of the later cladding and the breaking up of the existing concrete floor. The groundworker found that much of the sub-base beneath the old floor was sound and could be re-compacted, which reduced the quantity of MOT Type 1 needed. The new slab was poured in week two using the ballast and cement from our first drop.

Weeks three to eight were dominated by the brickwork. The bricklayer worked along the north wall first, then returned along the south wall, building the inner block leaf and the outer brick leaf together. The four cavity lintels were installed as the openings were formed, and the cavity insulation slabs were pushed in behind the bricklayer as each section was completed.

The roof phase ran from week eight to week eleven. After the old tiles had been lifted and salvaged, the carpenters repaired the rafter feet and fixed the OSB3 deck over the breathable membrane and counter-battens. PIR boards were laid on top of the deck before the reclaimed tiles were re-laid. By week eleven the building was weathertight, shielding the new brickwork and internal framing from the autumn rain that followed.

The final three weeks were given over to first fix, internal joinery and the holiday-letting fit-out. The fourteen sheets of hardwood plywood were used for window boards, shelving, the kitchen island carcase and bathroom boxing. We supplied a few small top-ups of screws and nails during this phase. Building control signed off the project in week fourteen, and the property was photographed and listed for short breaks shortly afterwards.

The result

The converted barn is now a holiday let with a long open-plan living space, two bedrooms, and exposed timber posts that give the interior its character. The external brickwork matches the repaired plinth, and the roof profile follows the original agricultural line. The first guests arrived in mid-October, on the date the client had targeted.

Kennet & Avon Homes told us that the staged brick deliveries were the key to keeping the site manageable on such a narrow plot. They also valued the fact that we inspected the hardwood plywood faces before delivery, because any damaged sheet would have been visible in the finished joinery.

The site finished with only a small surplus of bricks and timber, most of which was credited back. The lane and the neighbouring verge were left clean, and the builder reported no complaints from nearby residents about delivery disruption.

Star Hawk supplied the structural and insulation pack for £17,350, with the value coming from the staged delivery plan and the quality control at our yard. Kennet & Avon Homes billed the client for the overall conversion.

What we don't supply on a barn-conversion

On this Slough holiday let, the elements beyond our structural and insulation range were arranged by specialist contractors. The structural engineer produced the calculations for the new floor slab and any beam supports, and a local joiner supplied the oak facing pieces and any specialist timber repairs. The clay roof tiles were reclaimed from the existing roof and topped up where necessary.

Glazing, external doors and ironmongery were supplied and fitted by a fenestration specialist. The M&E contractors handled the electrics, plumbing, heating and ventilation. Kitchen and bathroom fittings, internal plasterboard and skim, floor screed, decoration, soft furnishings and the fire-safety and holiday-letting compliance certification also sat outside our range. We timed our structural deliveries to keep out of the way of these trades, while the specialists selected and installed their own materials.

Cost transparency

We priced the Slough Barn conversion to holiday let line by line from the quantities above. The materials Star Hawk supplied came to £17,350 and broke down as follows:

Category	Materials supplied	Cost
Masonry	1767 blocks Aircrete Blocks and 12326 bricks Hampton Rural Blend Brick	£9,150
Timber & sheet materials	1.6 cubic m C24 Timber, 228 linear m BS Treated Battens, 38 sheets OSB3 Board 18mm and 14 sheets Premium Hardwood Plywood	£2,950
Aggregates & sub-base	6 tonnes MOT Type 1 Aggregate, 19 tonnes Building Sand and 15 tonnes 20mm Ballast Aggregate	£1,640
Insulation	38 sheets Cavity Insulation Slab and 16 sheets PIR Insulation Board	£1,560
Cement & mortar	197 bags General Purpose Cement	£1,480
Lintels & steel	4 lintels 100 mm cavity steel lintel	£300
Fixings & hardware	14 boxes Galvanized Nails and 8 boxes High Performance Wood Screws	£270

The remaining cost on the Slough barn conversion covered the reclaimed or matching roof tiles, any steel frame repairs, glazing, M&E, kitchens, bathrooms and specialist finishes sourced by the contractor. That split is normal for a Slough barn conversion: we fix the price of the structural shell, while the finishing trades choose the items that need specialist selection or installation.

Why Slough homeowners choose Star Hawk

Our regular route serves the SL1 and SL2 postcode districts, the surrounding Berkshire villages and the towns along the M4 corridor. Most orders reach the site same day or next day on our own lorries, with one account manager looking after the account from first quote to final invoice.

We keep the structural range that barn conversions need in stock at our yard: MOT Type 1, cement, building sand, ballast, Aircrete blocks, facing bricks, cavity and steel lintels, C24 timber, treated battens, OSB3, PIR insulation, cavity insulation slabs, plasterboard and fixings. Our fleet ranges from 3.5-tonne to 18-tonne, so we can choose a vehicle that fits a narrow lane on the edge of Slough rather than sending an oversized wagon.

We take full ownership of every delivery. If a load is short, damaged or off-specification, we resolve it on our own account rather than leaving the site manager to pursue a manufacturer or third-party haulier. That matters on a conversion where a large brick order or a marked sheet of joinery plywood cannot be allowed to arrive wrong.

Most of our Slough customers are builders, developers and homeowners who want a written quote covering the full structural schedule, stock they can depend on, and a supplier that sends a vehicle sized for the access. If that describes your Slough barn conversion, send your drawings, schedule or bill of quantities through the quote builder and we will come back the same business day with a price and a delivery plan.

Whether it is your first barn conversion or one of several holiday lets, the process stays the same: send the schedule, receive a written quote, and get your materials on our own lorries when the programme needs them.