All structural timbers shall be preserved in accordance with BS 5589 (1989) code of practice for preservation of timber.
All components are to be softwood to stress class 3, as described in BS 4978 (1973) timber grades for structural use.
All structural fixings to be galvanised or rust protected..
Soleplates are supplied loose in random lengths preservative treated. To be fixed using "Bat" or similar galvanised soleplate anchors, spacing of nails to be determined by engineers calculations, usually at 1200 mm centres.
Timber frame panels comprise of top and bottom rails, with studs at centres to be determined by structural engineer. Rails are fixed to studs with at least 2 No 90 mm long (minimum) nails, offset to reduce the risk of splitting. Openings have lintels supported on cripple studs (sizes of lintels to be determined by structural engineer). The number of cripple studs to be determined by structural engineer. All external panels require sheathing of 7.5 mm Vanerply, 9.5 mm thick CDX plywood, 9 mm OSB board or 15 mm Bitvent fixed with 3 mm diameter nails at least 50 mm long placed at 150 mm centres around the edge of each sheet and at 300 mm centres internally. Tear proof breather membrane to BS 4016 (1972) prefixed to the external face of the sheathing (except Bitvent) with nylon tape to indicate stud positions, with 100 mm horizontal laps and 150 mm vertical laps.
Non-Load bearing panels to comprise top and bottom rails, with studs at centres to be determined by structural engineer. Rails are to be fixed to studs with at least 2 No 90 mm long (minimum) nails, offset to reduce risk of splitting.
Load bearing internal panels are to comprise top and bottom rails, with studs at centres to be determined by structural engineer. Rails are to be fixed to studs with at least 2 No 90 mm long (minimum) nails, offset to reduce the risk of splitting. Panels should have noggins (dwangs) fixed centrally between studs. Openings to have lintels supported on cripple studs (size of lintels to be determined structural engineer). The number of cripple studs to be determined by structural engineer.
In certain cases it may be necessary to fix sheathing to the panel for racking purposes
Additional studs are provided at all junctions and below trimmers, beams and girders etc.
The structural design is carried out in accordance with the requirements of BS 5268 part 2 (1996) and takes into account loading specified in BS 6399. All joists are of size, grade and centres to comply with Building Regulations.
Roof Components to be manufactured in accordance with BS 5268 Part 2 (1996), and BS 5268 Part 3 (1996) by our in house truss manufacturer, including all necessary drawings and calculations.
Manufactured as external/internal panels to match roof profile.
Cavity barriers shall be fixed around all openings, comprising 50 x 50 mm treated softwood battens with DPC fixed to the face of the abutting brickwork. Cavities to be closed using 50 x 50 mm nom treated softwood cavity closers. 50 x 50 mm preservative treated softwood fire checks to be fitted at all changes of direction and at 10mts maximum centres also at every floor level
rbrownandsons.co.uk - Created by C S Lamb