Bernard Barker's design for the social shed 12 Dec 2018
Following are drawings and cost estimates provided to RB by Bernard on 12 Dec.
Note that costs do NOT include trade discount, the amount of which will only be made available when an order is placed. It is therefore expected that the following costs may end up being up to 20% lower (Bernard has a trade account at Selco).
Foundations will use standard 'dense' concrete blocks (H)100mm (W)215mm (L)440mm on a bed of sharp sand on compacted soil. The original 'wooden' shed footing will be retained. (click on pdf to see design).
Total cost (inc VAT) = £75.00
The base consists of '4 by 2' (i.e. 100x47mm) treated timber floor joists with 50mm insulation board between supported on 19x38 battens.
Toptal cost (inc VAT) = £910.22
Walls are constructed as a number of separate 'panels' that can be individually fabricated in the workshop and then screwed together on site. The panels are designed to use the 2m long, '4 by 2' timber that was donated to us by Elliotts. The panels will have 9mm OSB3 board on the outside. When all screwed together a vapour barrier and log lap cladding will be attached to the outside.
Note that the new building will abut to the existing workshop but will still have a side wall constructed in the same way as the other walls.
Cost of the materials to this point is £1372.62 (inc VAT)
Internally, the walls will be insulated with 'rockwool' fibreglass matting with a 9mm plywood internal finish.
Cost of insulation and plywood is £521.68 (inc VAT)
Doors and windows are UPVC. There will be 3 windows 1000 (H) by 1200(W) and a single width door 2100 (H) by 1000 (W)
Online quote gives cost of windows and door as £897.32 (inc VAT)
The roof consists of '6 by 2' (i.e. 147x47mm) rafters on top of which is glued 11mm OSB3, 25mm insulation board and a 9mm OSB3 top layer.
Note: this is a 'cold roof' design. A 'warm roof' design (i.e. with insulation between the rafters is a possible alternative.
Total cost of the roofing components is £997.24 (inc VAT)
The final coating on the roof will be a professionally installed hot sealed 3 coat felt.
At the moment, we do not have a firm estimate for this item.
Electrics are estimated to cost £636.12. This is based on similar lighting to the workshop, 7 double sockets and two portable heaters.
Windows and Door