Loft conversions - Building Regulations

Building Regulations applications, from the local authority, are applicable for any loft conversion that turns storage space into living space.

The Regulations are not the same as planning permission, the ensure that the work conforms to health and safety standards and that the work has been carried out correctly. Work using incorrect materials could mean that selling the property in the future is not possible.

They cover areas such as structural stability, access, fire resistance, weather resistance, means of escape, energy conservation and ventilation.

To ensure that a loft conversion will conform to the Regulations a full set of plans should be submitted to the local authority if requested.

Structural Stability

Floors

Using the loft as a room to be lived in rather than storage will mean new ceiling joists as existing ones will not be able to carry the load.

This could introduce the need for steel beams, which must be installed by a qualified builder. Calculations on the load-bearing properties of the beams need to be checked by the local authority, and must include the overall stability of the roof and the implications of adding features such as dormers and skylights and how weight will be redistributed.

The floors and beams must be fire resistant for at least 30 minutes.

Walls

New walls or floors must sit on load bearing walls with a proper foundation. This very basic requirement cannot be underestimated - failure to comply could mean redesigning and starting again!

The loft conversion must be separated from the rest of the house by a fire resistant wall and door (again 30 minutes is the minimum standard). If the wall of a dormer is within one metre of the boundary of a neighbouring property, the fire protection should be applied internally and externally.

The walls must be treated with a weather resistant finish. Thermal insulation to external walls should achieve a U-value of not more than 0.35W/m2mk, for roof areas the U-value achieved must be no more than 0.30W/m2oK.

Stairs

Most local authorities prefer stairs to loft conversion to be a traditional straight flight, although other alternatives may be considered if space is at a premium.

Handrails and guarding are essential Headroom needs to be not less than two metres. Again the stairwell needs to be enclosed, and as with the doors, needs to be fire resistant for a minimum of 30 minutes.

Ventilation

Ventilation is necessary for a healthy living environment, it also helps to prevent condensation. Obstructing air-paths could lead to condensation problems - in areas under the roof tiles this could well go undetected.

Ridge vents to a continuous 5mm gap and eaves vents to a continuos 25mm gap should be built to front and rear unless a vapour permeable sarking layer (breather felt) is used.

A vapour check layer at ceiling level restricts the amount of water vapour entering the roof space from the loft conversion.

Dormers built with a warm deck roof ridge vents equivalent to a continuous 25mm gap must be installed.

Fire Escape

Escaping in case of fire would normally be by the staircase which must comply with Building Regulations to ensure it discharges to an exit such as the back or front door.

A window should be provided which allows enough space to escape through, and allow access by ladder (the minimum sizes are specified within Building Regulations).

Smoke detectors are required within seven metres of a kitchen or living room door and three metres of a bedroom door.

Information in respect of Building Regulations can be obtained from:

DCLG Free Literature, PO Box 236, Wetherby, L23 7NB or go to www.communites.gov.uk