loft conversions

Loft conversions are growing in popularity as more and more people recognise the potential they provide in adding value to property. Loft conversions don’t come cheap but in the long run they can significantly improve your home. Throughout this site there is reference to the building regulations that all loft conversions need to comply with. Where the existing roof construction is to be altered, the roof must continue to be adequately supported usually via load-bearing studwork onto load-bearing elements such as internal walls or new steel beams. To ensure that the existing structure is suitable for carrying additional loads of the loft conversions, it may be necessary to dig trial holes to check the existing foundations to internal and external walls, and it may be that existing lintels will need to be replaced. It is unlikely that the existing ceiling joists will be adequate for the new floor loading and new joists will need to be inserted (these may be laid between the existing joists). Their size will be dependant upon the spans involved in the loft conversions and if supporting additional loads such as the roof/stud walls then calculations will be required.

The loft conversions should have adequate thermal insulation, again in accordance with current Building Regulations. This can be achieved in a manner of different ways and advice should be sought from the Area Building Control Surveyor. As a result of providing insulation into the sloping sections of a roof, adequate cross-flow ventilation must be achieved to avoid the risk of condensation in the loft conversions. New windows must be double glazed and meet current standards for U-Value requirements. For ventilation purposes the opening area must amount to a minimum 1/20 of the floor area of the room served and background ventilation by way of trickle ventilation is required, a minimum of 8000mm² for habitable rooms, 4000mm² for bathrooms. Sound insulation in the loft conversions should be provided using a minimum thickness of 100mm of mineral wool having a minimum density of 10Kg/m3, laid between the new floor joists.