EXTENSIONS: How to get flat roofs right
For many smaller extensions, a flat roof can provide a simple, cost-effective solution that ticks all the right boxes. Their comparative ease of construction and discreet visual impact can save having to shell out for a more expensive tiled roof in many cases. Flat roofs can also come in handy where a bulky pitched roof on an extension would overshadow or block existing windows. There may even be an added bonus where the space can be utilised as a balcony, subject of course to planning and Building Regulations.
The main downside is that flat roofs have gained an unenviable reputation over the years for developing problems. Unless carefully designed and constructed they are notoriously prone to leakage and heat loss, along with defects like sagging decks, ponding water and prolific plant growth. Which may explain why insurers tend to be wary of properties endowed with large areas of flat roofing. Thankfully such concerns can be dispelled by taking the trouble in advance to consider the three main aspects of flat roof design: the structure, insulation and coverings.
The structure
Extension flat roofs are normally constructed like timber floors, in essence comprising a series of joists with a timber deck plonked on top. Obviously,.)
