Building Regulations state that when refurbishing or replacing an existing flat roof covering, the replacement system must also make provision for an upgrade to the thermal properties of the roof. Nothing like two more decades of experience to draw on. I just didn’t get around to doing the second part - rigid insulation over the top of the existing roof deck. Compliance with current building regulations . Due to a rewire I've had to remove parts of the plasterboard ceiling and have found that there is no insulation in the roof - I can see the roof deck and joists, there is no vapour layer and the plasterboard is not foil-backed. Most of it covers a garage which does not need insulation, but some of it also covers interior rooms which get very hot in the summer and cold in winter months because there is no insulation. Install roofing underlayment, flashing, and cladding as per best practices. Flat roof – there are three options available: warm deck, cold deck or inverted roof. Discussion in 'Builders' Talk' started by cobra11, Jan 11, 2010. cobra11 New Member. Use Premade Roof Trusses Premade roofing trusses will be easier and take less time than installing a stick-built roof. 1. Flat roof. Nailbase must be vented in high snow-load areas. If you live in an old house, you know how drafty it can get in the winter. For the last 10 years or so most new build flat roofs are constructed using a “Warm Roof System”, simply put; this involves fixing solid insulation boards to the top of the flat roofing deck and by doing this you completely eliminate the need to ventilate between the joists and therefore cold air circulating and plunging into your home causing draughts and cold spots. By creating appropriate falls and drainage, a flat roof is more likely to last for its designed life by channelling water to outlets efficiently. The panel adds a remarkable amount of structure as well as insulation to the project. Reduce extreme temperature fluctuations inside your home. These Flat Roof sections are often braai rooms or additions to an existing roof. Generally, a minimum of 4 fixings should be used per 1200 x 600mm board, but this should be calculated in accordance with BS EN 1991- 1–4 to be site specific. Insulation is required to minimise heat losses in the winter and control excessive solar gains in the summer. The insulation plus for roof renovation. By this time I had it figured out. Lay board insulation bonded to the top of the roof and refelt,much easier. It is the opposite to a warm flat roof as the insulation is inserted below the deck, but above e.g. Insulation. Hi all My kitchen extension has a solid concrete roof 4" thick. This often means the home has no Roof Insulation this, in fact, will make the home very hot in summer and very cold in winter. Insulation is placed over and between the wooden joists, above the ceiling of your home's top floor. This is placed over the roof joists and an board (normally external ply) is laid on top. With a duo/plus roof, an additional layer of thermal insulation and a subsequent layer of gravel are installed on top of an existing standard non-ventilated flat roof construction. Insulation can also help to limit condensation and contribute to acoustic insulation (depending on the type of insulation used). The roof is sound with no leaks or faults but has no insulation. Flat Roof - Insulation. However, this will be £££ as you will need to strip the roof back to some extent then felt over the insulation boards. Compared to the fiberglass batts, this insulation is much better. We offer a versatile range of premium-quality stone wool roof products – providing excellent thermal, acoustic and fire-resistant solutions for both commercial and domestic projects. Apply the appropriate mechanical fixings or using hot bitumen. Having Flat Roof Insulation Installed in these homes makes a huge difference in the heat flow into the home. Would agree with BC. Hot roof . The installation of a warm roof with rigid insulation on top of a damp proof membrane, prevents condensation without the need for ventilation. In fact, some homes are built with ceiling and roof pitch very flat. Cold roof – a very bad idea! the plasterboard. If you’re having your roof replaced, adding insulation on top of the existing roof deck is the easiest way to boost the R-Value of your home, save some money, and create a more comfortable living space. I'm looking for possible options to insulate a flat roof. concrete flat roof insulation. your roof type (flat or pitched) its structure (depth of the rafters) your willingness to invest; In most cases, extra investment made in beating the Building Regulations on insulation is money well spent — it gives a lot back in returns. Go Green, Save Green. Financially speaking, this spray is a great option especially when you need to renovate your roof after the application. Insulating a roof is perhaps the easiest of all the energy-saving home improvements. The boards can simply be installed on top of the existing waterproofing layer. Tapered insulation is also ideal for existing roofs that may not already incorporate a structural fall. The fact that a roof looks in good condition should not be the basis of installing a new roof covering. It is more popularly known as Hypalon. For a flat roof, you will need to check for waterproofing as well and make sure the existing roof structure is not damaged, as the requirements for insulation will be different if there is damage. Homes with flat roofs require a different approach to insulation than the standard approach used for homes with pitched roofs. Types of garage roof – Warm or Cold. To produce a hot roof, rigid insulation is fitted outside, above the weatherproofing. 1 Strip the shingles, expose the deck, install a fully adhered membrane and go to town with rigid insulation. I have a flat roof on my property which is uninsulated. Flat roof insulation can easily create leaks, moisture and damp if not done properly. I have a (very sligthly sloped) flat roof deck held up by 2x8's to which the ceiling for the upstairs room is attached. A cold flat roof is a roof that has been insulated from the inside, below the roof joints. A flat roof is defined as any roof that has a pitch of less than 10 degrees. At MHTflatroofing we are experienced at fitting flat roof insulation. This would be the perfect option if you are looking to gain all the positives of a properly insulated flat roof such as saving you money and keeping you warm. Install nailbase for cladding. The spray can be basically applied on top or bottom of the metal roofing surfaces. Cold loft insulation for pitched roofs. Flat roof insulation projects can be undertaken by capable DIYers looking to top out a garden building or small extension but we would recommend that if you’re not fully confident with the process as above that you consult or employ a professional to undertake the work. Of your email interested please feel free to contact us on Facebook at CP MillWorks business page. If this is in a good condition, then it can just be swept clean and the insulation either mechanically fixed or glued on top of the existing roof. Adding insulation to an existing flat roof generally requires the removal and replacement of some of the existing structure. The spaces are 9" deep on 16" centers. building control, Apr 7, 2006 #3. trench New Member. 4. Any insulation experts on here? When you have an un-insulated roof, you have to live with rather uncomfortable room temperatures inside the home. Lay the Mannok roof insulation boards on top of the vapour control layer with joints staggered between rows. We have done many roof retrofits with a structural insulated panel nail base panel. Is it possible to overlay an existing flat roof with Single Ply? How much rigid insulation? The cheapest option would be to leave the old roof in place and place the new rafters over the existing roof. The one you finally choose depends on several factors, such as the arrangement of the layers of particular materials, the way the roof slope is used, and the type of roof. Flat roof insulation — what does it depend on? CSPE Chlorosulfonated Polyethylene is a synthetic rubber roofing material. Then a waterproofing layer can be added on top of this. Warm deck: the type of insulation for this is usually of a rigid type and the thickness will vary depending on the manufacturer's specifications. Therefore, the space between the ceiling and the roof deck is about 7 inches - much like a cathedral ceiling, except that it's basically flat. A cold flat roof is often ventilated below the water proofing part of the construction. We use 100/120 mm PUR insulation boards, that work extremely efficiently and can usually be fitted on top of an existing cold roof by adjusting the fascias. What is flat roof insulation? Make sure the pitch of the trusses is the pitch that you want for your new roof. It is not normally possible to spray or blow insulation into an existing void or attach insulation to the underside. In practice a flat roof is pretty easy to spot because essentially it is horizontal. While insulation for a flat roof is expensive and can account for as much as 25% of the total installation cost, there are a number of important benefits to having it in place. We go right over the existing shingles. There are ventilation issues with insulation fitted from underneath. How to Improve Insulation Levels of Flat Roofs. This cold weather has shown up the problems with it. Premade trusses will form the skeleton of your new roof above your old roof. The basic decision to make when it comes to thermal insulation of a flat roof is the material. Freezing cold kitchen and condensation dripping down. There is around 15cm between the top of the ceiling plasterboard and the underside of the felt. Ventilation is required for these roofs. There are two different methods of insulating a roof that vary on the basis of roof structure. This will help to conserve energy and ensure thermal comfort is maintained within the building. Upgrading insulation on a refurbishment roof Building regulations. The simplest and cheapest roof insulation is the classic cold loft option. This is then covered with a further weatherproofing layer. Mostly the answer is yes, but each project should be taken on its own merits. Hi, I have a flat roof extension built in the 1970s. Use kinspan or celotex to form a warm deck roof. How to Install Insulation Board Over an Existing Roof Membrane. For warm flat roofs, where insulation is added above the roof joists, the first area to check is the condition of the existing waterproofing on the roof. A flat roof is a roof which is almost level in contrast to the many types of sloped roofs. Or call at 316-995-1607! Pitched roof – there are two options: warm or cold loft insulation. 1. The insulation capacity of a 10cm thickness of batts is as same as 10cm of polyurethane foam. Also flat roofs don’t tend to have the loft space that you normally associate with pitched roofs, so on the whole they won’t have the loft hatch in the ceiling. Cold roof systems are highly inadvisable as insulation from the inside will inevitably lead to the formation of condensation. Flat roof insulation is crucial for improving energy efficiency, comfort and living standards in buildings. 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