I'm gonna do a loft conversion on my victorian end of terrace house. Planning Application has been approved. Now I have to get the building control application in. However, I need to detail out the specs and have reached the boundary of my skills.
This is what I have done. Can you let me know if what I have makes sense. Or which bits don't make sense.
Many thanks,
RichA
Loft Conversion
GENERAL
All dimensions to be checked on site. Drawing is produced for the purpose of local authority approval and does not include heating, electrics & decoration.
PITCHED ROOF
Raise existing ridge level by 500mm. Extend existing rafters to obtain internal height of 2300mm. Bolt new rafters to existing with minimum overlap of 1.0m and bolt at apex to new timbers with M12 bolts. To existing roof areas grey slates on 50mm x 25mm battens on roof felt on rafters. Provide roof insulation between rafters. Allow 50mm air gap over for ventilation.
ROOF VENTILATION
Min. 50mm air gap over insulation. Provide vents to eaves (front & rear) equal to 25mm continuous strip. To ridge provide either ventilating ridge tile or min. 4 venting roof tiles to each side of roof equal to 5mm continuous strip. Flat roof is a warm construction and needs no venting.
PARTY WALL
Raise party wall in second hand London stock bricks to match existing.
FLAT ROOF
12mm mineral chippings on three layers of roof felt on insulation on vapour barrier on 18mm WBP ply deck on firings on 150mm x 50mm SC3 joists @ 400mm o/c. Finish ceiling with 9.5mm plasterboard & skimcoat.
MANSARD / DORMER WINDOW
Grey slates to match main roof on battens on sarking felt on 18mm external grade plywood on 150mm x 50mm stud work frame @ 400mm o/c and 70% pitch. Voids between framing to be filled with celotex insulation. Vapour barrier attached to studs. Walls finished with 12.5mm plasterboard & skim.
INTERNAL STUDS
100mm x 50mm studs @ 400mm o/c with solid noggins @ 800 o/c. 100mm celotex insolation to be set between studs on external walls. Studs to be finished plasterboard & skim coat (12.5mm plasterboard around stairwell & 9.5mm elsewhere.
STEELS BEAMS
All new steel beams specified by to Structural Engineer (see separate Structural Engineer Drawings & Calculations).
FLOOR STEEL PROTECTION
Floor steels coated in intumescent paint to provide full half hour fire protection.
ROOF WINDOWS
Provide two Velux GGLM06 (780mm x 1180mm) windows to main room. Double joist trimmers bolted with M10 bolts. Trickle vent.
MEANS OF ESCAPE
Provide roof escape window Velux GPL M06 (780mm x 1180mm) to front roof, max. 1700mm from eaves level and min. 600mm from floor level. Rafters around window to be doubled up.
DAYLIGHT/VENTILATION
Windows to be double glazed. New rooms to be provided with background ventilation. Mechanical vent to new bathroom. Any windows below 800mm from floor level to be toughened glass to BS6206. No door glazing. New glazing to be in low E glass.
NEW STAIRCASE
14 treads @230mm, 15 risers @200mm (to be checked on site). Headroom to be min. 200mm above pitch line. Max gap between banisters to be 100mm. Handrail to be min. 900mm above pitch line.
FLOOR
Fitted with 18mm tongue & groove floor grade chipboard, waterproof in bathroom, on 175x50 joists @400mm o/c. Joists to be supported by main steel beam & interval load bearing walls. Noggins to support existing joists.
LOFT VOID
Eaves area void / storage space to be boarded as main floor.
DRAINAGE / WASTES
All traps 75mm deep seal. Bath waste 50mm round. Basin waste 32mm round. WC waste 100mm round to existing soil stack.
SURFACE WATER
100mm ½ round PVC guttering to 68mm round matching downpipes to discharge onto main roof and into existing s/w system
MECHANICAL EXTRACT
Provide mechanical extract to bathroom (minimum 85 m3/hour with overrun).
SMOKE DETECTION
Smoke detectors (linked mains with battery backup) to be provided on first & second floor (i.e. first floor kitchen – heat & smoke, second floor (loft) hall - smoke).
ELECTRICAL INSTALLATIONS
In accordance with current IEE regulations & codes of practice.
This is what I have done. Can you let me know if what I have makes sense. Or which bits don't make sense.
Many thanks,
RichA
Loft Conversion
GENERAL
All dimensions to be checked on site. Drawing is produced for the purpose of local authority approval and does not include heating, electrics & decoration.
PITCHED ROOF
Raise existing ridge level by 500mm. Extend existing rafters to obtain internal height of 2300mm. Bolt new rafters to existing with minimum overlap of 1.0m and bolt at apex to new timbers with M12 bolts. To existing roof areas grey slates on 50mm x 25mm battens on roof felt on rafters. Provide roof insulation between rafters. Allow 50mm air gap over for ventilation.
ROOF VENTILATION
Min. 50mm air gap over insulation. Provide vents to eaves (front & rear) equal to 25mm continuous strip. To ridge provide either ventilating ridge tile or min. 4 venting roof tiles to each side of roof equal to 5mm continuous strip. Flat roof is a warm construction and needs no venting.
PARTY WALL
Raise party wall in second hand London stock bricks to match existing.
FLAT ROOF
12mm mineral chippings on three layers of roof felt on insulation on vapour barrier on 18mm WBP ply deck on firings on 150mm x 50mm SC3 joists @ 400mm o/c. Finish ceiling with 9.5mm plasterboard & skimcoat.
MANSARD / DORMER WINDOW
Grey slates to match main roof on battens on sarking felt on 18mm external grade plywood on 150mm x 50mm stud work frame @ 400mm o/c and 70% pitch. Voids between framing to be filled with celotex insulation. Vapour barrier attached to studs. Walls finished with 12.5mm plasterboard & skim.
INTERNAL STUDS
100mm x 50mm studs @ 400mm o/c with solid noggins @ 800 o/c. 100mm celotex insolation to be set between studs on external walls. Studs to be finished plasterboard & skim coat (12.5mm plasterboard around stairwell & 9.5mm elsewhere.
STEELS BEAMS
All new steel beams specified by to Structural Engineer (see separate Structural Engineer Drawings & Calculations).
FLOOR STEEL PROTECTION
Floor steels coated in intumescent paint to provide full half hour fire protection.
ROOF WINDOWS
Provide two Velux GGLM06 (780mm x 1180mm) windows to main room. Double joist trimmers bolted with M10 bolts. Trickle vent.
MEANS OF ESCAPE
Provide roof escape window Velux GPL M06 (780mm x 1180mm) to front roof, max. 1700mm from eaves level and min. 600mm from floor level. Rafters around window to be doubled up.
DAYLIGHT/VENTILATION
Windows to be double glazed. New rooms to be provided with background ventilation. Mechanical vent to new bathroom. Any windows below 800mm from floor level to be toughened glass to BS6206. No door glazing. New glazing to be in low E glass.
NEW STAIRCASE
14 treads @230mm, 15 risers @200mm (to be checked on site). Headroom to be min. 200mm above pitch line. Max gap between banisters to be 100mm. Handrail to be min. 900mm above pitch line.
FLOOR
Fitted with 18mm tongue & groove floor grade chipboard, waterproof in bathroom, on 175x50 joists @400mm o/c. Joists to be supported by main steel beam & interval load bearing walls. Noggins to support existing joists.
LOFT VOID
Eaves area void / storage space to be boarded as main floor.
DRAINAGE / WASTES
All traps 75mm deep seal. Bath waste 50mm round. Basin waste 32mm round. WC waste 100mm round to existing soil stack.
SURFACE WATER
100mm ½ round PVC guttering to 68mm round matching downpipes to discharge onto main roof and into existing s/w system
MECHANICAL EXTRACT
Provide mechanical extract to bathroom (minimum 85 m3/hour with overrun).
SMOKE DETECTION
Smoke detectors (linked mains with battery backup) to be provided on first & second floor (i.e. first floor kitchen – heat & smoke, second floor (loft) hall - smoke).
ELECTRICAL INSTALLATIONS
In accordance with current IEE regulations & codes of practice.
