Roof replacement or repair

Much of South Africa’s housing stock is in the older suburbs, which were established before or soon after the Second World War.   These houses are now 60 years old – or even older.    Roof replacement – either of just the roof covering, or the entire roof structure – becomes a possibility for these homes – especially if the roof has not been properly maintained over the past half century.

Regular monitoring of the roof covering and timber structure, combined with timely maintenance will prolong the life of a roof.   However, if roof sheeting has been allowed to rust; if tiles or slates are broken, if flashing has failed and if water has penetrated the roof cavity, then ultimately it may be more cost effective to replace rather than repair the roof.    There comes a time when ongoing maintenance costs may exceed that of replacement.

HouseCheck home inspectors are trained to evaluate a roof structure and advise whether maintenance and repair or replacement is the best option.

Signs of a roof in distress include a plethora of leaks – old and new – and a sagging roof.

Replacement of a roof offers the opportunity for house owners to consider different roof coverings.  Possibilities include high-tech coated metal sheeting, new clay or concrete tiles, fibre cement slates, or bituminous shingles laid on a board substrate.   Changing the roof covering can dramatically alter the look of the house and its thermal qualities. 

A good roofing contractor will assess the ability of the existing structure to accommodate the load of the covering.

Replacing a roof also offers an opportunity to properly insulate the roof space.   Old South African roofs are rarely properly insulated.   In winter the heat from the home escapes through an un-insulated roof space and in summer the air in the same roof cavity usually becomes extremely hot and heats up the rooms below.

Insulation options which can be considered if a roof is to be replaced include:

• Installation of an insulating and moisture-proofing membrane – usually a combination of plastic and aluminum – directly under the roof covering.
• Installation of roof ventilation.
• Ceiling insulation.

Home owners should select a roofing company with a proven track record, because the replacment of an existing roof is a tricky and demanding undertaking.   Depending on the structure it may well be possible to replace the roof covering without interfering with the ceiling, interiors and electrical and plumbing installations.  A good roofing contractor will be able to advise in this regard.

If the existing roof is asbestos sheeting or slates, then a roofer who is also an approved asbestos removal contractor is required.

Re-roofing involves working at heights and is dangerous if the contractor and workmen are not experienced.   Home owners are ultimately responsible for the safety of workmen on their property.   Unless the building contractor is properly insured and registered, the home owner may be liable for costs and claims resulting from injuries or deaths during the re-roofing process.

It is therefore important for home owners to properly screed contractors before awarding them any construction work.