Warm & Cold Roofs
Whether you are building a new extension or refurbishing and old ﬂat roof, it is important to consider insulating a roof to meet new building regulations and increase energy efficiency.
Regal Rooﬂines can not only carry out hot and cold roof installations but can advise you on the advantages and beneﬁts of both solutions.
By insulating your roof using a ‘warm roof’ technique, you not only dramatically increase your energy efficiency but keep your house warm in the winter and cool in the summer!
Traditional “Cold Deck Insulation”
Traditionally, flat roofs are formed of single timber board or “deck” with a waterproof covering fitted to the top of the board.
This outdated design is somewhat archaic and harks back to a time when insulation of all types was simply an afterthought.
A cold flat roof does include insulation typically by way of kingspan or celotex insulation material inserted between joists.
This wool is packed into the joists and rafters a clear gap of 5cm is left between the insulation and the timber board to allow condensation to escape this is to prevent the condensation making contact with the boarding or deck…. giving rise to the name cold deck insulation.
Cold deck insulation needs to be externally ventilated to prevent rotting. Water simply must be prevented from collecting on the timber deck.
Although essential the need for this venting commonly known as draught venting this system has one unwanted effect; it is incredibly inefficient and as such the heat lost is considerable.
Aesthetically this venting system can be quite offensive as these vents will be quite apparent and may even jut out from the surface of the roof.
The solution “Warm Deck Insulation”
Fortunately these days there is a better form of insulation available for your flat roof. This system is called warm deck insulation and eradicates the condensation and venting issues associated with the cold deck system.
The layer of insulation is essentially placed outside of the roof. This, in turn, means the deck is sealed off; effectively placing the deck inside making it completely free from the dangers of condensation and the associated rotting commonplace with cold roof insulation.
The insulation material itself is polyisocyanurate foam which is finished with a specialist foil fitted to either side. Put simply the concept behind this design is ingenious as it provides over twice the heat retention when compared to the old style thermal mineral wool.
Not only will this type of warm deck insulation keep you warmer it is also far kinder to both your pocket and the environment.
Flat Roof Insulation And The Law
The right type of insulation will keep you warm in the Winter and Cool in the Summer while at the same time reducing fuel bills.
Since the mid-2000s and the inception of the conservation of fuel and power building regulations, the legal requirements around flat roofs have changed. These days all new build flat roofs must adhere to these specific requirements. All new flat roofs are then tested by local building officials. Find out more about fibreglass flat roofing,