Take a look at some some images and a video of a loft being constructed. Courtesey of Charles Grosvenor Ltd.
Typical loft conversions use steel RSJs (rolled steel joists) to support the weight of the new floor. This conversion is very typical and requires two steel RSJs to support the new floor and the rafters by way of a dwarf interior wall (ashlaring wall). A loft conversion can be made entirely from timber joists but the increased costs (materials and labour) mean that just about every loft conversion uses steel beams nowadays. The steel RSJs are prepared to take the new floor joists by bolting timber joists into the 'I' of the beam.
When the steels are in place work can start on removing the trusses and putting in the additional timber work that will transfer the roof load down onto the new chipboard floor. Stud work is put up at this time to form the new rooms. Any water tanks that would have been present were removed and capped off. Note the VELUXs are already in now and the window aperatures ready in the new dormer and the multi foil insulation has been fitted.
Dormer cheeks constructed of 18mm OSB Board and covered with breathable felt. Roofing batten then fixed prior to having the tiles put on, readily matched to the existing type once the windows have been installed. These are typically uPVC double glazed to meet all guidelines and U-values required.
Installing the staircase is a major milestone in the conversion process as it connects the loft space to the rest of the house and the loft now starts to feel like another room. Building guidlines insist that for safety and as a means of escape the stairs are permanent and not a loft ladder or other removeable set of steps. The pitch of the stair shouldn't rise above 42 degress with a tread going no less than 220mm and a rise no more than 220mm to obtain this. A minimum of 50mm around the newel posts is also required as set out in Park K of building regulations.
Note the addition of a VELUX overlooking the stairwell to let in more light. The plasterboarding and plastering is quickly wrapped up and left ready for the lights and heating to be connected and fitted once dry. Linked smoke alarms would have been installed throughout the house as set out in the guidelines. This eliminates the need for fire proof doors to be fitted throughout.
All finished. Plastered, painted and ready for use. Whether an extra bedroom or playroom the addition of loft conversion will not only give more room and comfort in your home, it will add value to the price as well.
More completed work for satisfied customers.