flat roof INSULATION

Protect Your Home From the Elements

As heat rises, the majority of energy is typically lost through the roofing area. Flat roof insulation is an important strategy for improving a building’s energy efficiency and lowering fuel expenses.

Creating more effective flat roof barriers also provides your structure with more protection against the unpredictability of the outer climate, such as overheating in hot areas and rain and snow in cooler climates.

Flat roofs are an essential feature of modern building design, from high-rise apartment buildings to residential designs, industrial units, big commercial facilities, and schools or hospitals.

Terraces, rooftop gardens, blue roofing with water retention, and roof areas utilized for solar purposes are becoming increasingly common. This rising trend for useful roof spaces increases need for good insulation, which contributes to the amount of space available on top of your structure.

Adding insulation can help ensure that your building is up to code. Call us today at (360) 265-3905 if you have any questions about foam insulation services.

What is Flat Roof Insulation?

Flat roof insulation is particularly cost effective when it comes to reducing overall energy consumption – and it is a critical, important investment for the future.

Furthermore, flat roof insulation has a relatively quick payback time in terms of money, energy, and carbon footprint.

There is no ‘one size fits all’ solution for how much flat roof insulation you will need. Because there is typically no limit to the installation height on a roof, and “the sky is the limit,” insulation thickness may be modified to practically any client specification and local regulatory energy demand.

Our flat roof insulation is available in a range of forms and may be easily customized to meet your design and architectural requirements. To minimize ponding water on the roofing membrane, Pacific Spray Systems’ ‘Cut to Fall’ solutions may be utilized to direct water to the roof’s outlets.

Why is it Important to Insulate your Roof?

Roof insulation is sometimes questioned by homeowners who are building or upgrading their houses. Installation of insulation installed directly into the roof slope is not necessarily typical, raising the question of need for many homeowners.

Proper flat roof insulation may not be found in every home, but it does offer benefits. It not only prevents unwanted damage, but it also keeps you from incurring significant heating and cooling bills during harsh weather. Poor or non-existent insulation is particularly expensive due to the amount of energy spent in attempting to keep a home at a comfortable temperature.

However, many homes just have ceiling insulation and no roof insulation. This is extremely common, and in certain cases, it can work well enough to eliminate the need for roof insulation in addition to an insulated ceiling.

Insulating a Flat Roof

Since its inception, flat roofs have proven to be a difficult undertaking for both builders and homeowners. They are difficult to waterproof, maintain, and insulate. We’ll continue with the insulation issue for the time being.

To adequately insulate a flat roof area, you must be very careful about the materials and procedures employed. For the sake of organizing, I’ll divide them into sections:

  1. Insulation Installed Between Ceiling Rafters

For this procedure, just two types of insulation need be employed. Spray foam insulation (closed or open cell) or dense-pack cellulose insulation Because air does not travel in a straight path, it is extremely difficult to adequately ventilate a flat room. This attracts moisture into an area, which, if trapped, can cause significant harm and is difficult to remove. It is significantly simpler and more efficient to create a non-ventilated compartment and fill the whole cavity with dense-pack cellulose, or to seal the region with 4 to 5 inches of spray foam.

Rafter height is one factor to consider. Due to R-value constraints, you will only be allowed to insulate with closed cell spray foam insulation if you only have 2×6 rafters (closed-cell foam is R-6 per inch, open-cell foam is R-3.5 per inch, and cellulose is R-3.8 per inch). If your rafters are at least 2×8, you can use dense-pack cellulose or open-cell spray foam.

2. Exterior Roof Surface Insulation

Insulating a flat roof from the outside is the most common approach for business roofs, but it may also be used for residential roofs. Applying a powerful glue to the foam board, placing it down on the roof surface, and fixing it with washer head nails accomplishes this. The rubber waterproof membrane is then applied to the surface of the foam board. To obtain the required R-value, two or more layers of foam board are often employed in this application. Again, no ventilation is required. The ceiling joist gaps may be left vacant in this application. Remember that if this approach is employed, the rim joists must still be insulated in order to maintain the insulation continuous from roof to wall and minimize moisture and air intrusion.

What’s The Difference Between Flat Roof and Ceiling Insulation?

The insulation of the actual roof slope is referred to as flat roof insulation. Ceiling insulation, on the other hand, refers to the installation of any sort of insulation in the floor closest to the roof structure. Insulating a ceiling is much easier and sometimes cheaper than insulating a roof, so if you have to pick between the two, ceiling insulation may be the best option.

Having said that, there are particular situations in which your roof must be insulated. Roof insulation is required in any property where the ceiling is part of the roof deck, such as cathedral ceilings, to regulate the internal temperature of the house.

Benefits of Flat Roof Insulation

For starters, a damp-proof coating is put to the roof structure to keep moist air from condensing in the insulating material. Flat roof insulation boards that are scarcely sensitive to shrinkage or expansion are installed on top of this membrane. Consider stiff boards made of styrofoam, EPS, PIR, or perlite.

To ensure proper rainfall drainage, the insulation boards should be put with a fall as much as feasible. Eventually, the roofing will be put on top of the flat roof insulation boards, acting as a water-repellent layer. Tiles or gravel can be used to complete the roof. It may be necessary to increase the roof edge depending on the thickness of the insulating material. In the event of severe rain, this should prevent rainwater from flowing over the roof.

Types of Flat Roof Insulation

Warm flat roof

When insulating material is laid on top of the roof construction, we refer to it as a warm flat roof. The most significant advantage of this method is the insulating material’s protective function. The roof and the space underneath it are gradually heated. As a result, the roof is less susceptible to drastic temperature variations.

The shrinkage- and expansion strain in the roof structure as well as the roof seal will be reduced. Another advantage of a heated flat roof is that it is still walkable, depending on the type of insulating material used (more or less). The warm flat roof is the most commonly used.

Cold flat roof

When insulating material is put on the bottom side of the roof boards, we refer to it as a cold flat roof. The area below does not heat the roof, and it is vulnerable to environmental conditions such as temperature variations induced by heat or frost. As a result, the roof structure and the sealing layer will shrimp or expand, causing damage over time.

As a result, as far as possible, a chilly flat roof should be avoided. However, owing to technical constraints, a warm flat roof structure is not always a possibility. In such instances, the cold roof concept can be used to insulate the roof, which is still preferable to no insulation at all.

Inverted flat roof

When renovations are carried out but the existing roofing must remain in place, an inverted flat roof is typically used. The insulation is put over the existing roof sealing. Eventually, the roofing will act as a water barrier. This insulation method’s thermal insulation value is inferior to that of a warm roof. An inverted roof, on the other hand, will be less expensive.

Frequently Asked Questions

What insulation is best for flat roof?

Roofing specialists underline the importance of selecting flat roof insulation with the suitable R-value. Polyisocyanurate (Polyiso) rigid foam is the most costly and highly recommended insulation. Extruded Polystyrene (XPS) and Expanded Polystyrene (EPS) are other excellent choices.

Warm roof or cold roof insulation?

A warm roof installation offers several advantages over a cold roof installation. It is more thermally efficient and, despite its greater construction cost, reduces overall heating expenditures, saving money in the long term. A flat roof installation does not require ventilation since warm air is trapped beneath the solid surface of the roof. Because there is no airspace between the roof and the warm air, no condensation occurs.

When creating a warm roof, the architect must consider the additional weight of the insulation. This is especially true in sloping roof residential buildings. Because a conventional sloping roof cannot support the added weight of insulation, stronger roof trusses must be employed.

How long does Flat Roof Insulation last?

Insulation materials are often quite durable. Flat roof insulation is expected to last between 25 and 40 years. It’s worth mentioning that because warm roof insulation is exposed to the weather, it degrades faster than cold roof insulation. This, however, should not be a reason for concern because the insulation will last at least as long as the strong waterproofing substance.

What is the minimum thickness for flat roof insulation?

The insulation’s resistance value (R value). Most commercial insulation has an aging R value of around 4 per inch. This varies according on the environment, and there are some installation concerns. There are certain outlier goods, such as factory foamed aluminum panels with R7 per inch, but these are uncommon.

Get in touch with Pacific Spray Systems for your Flat Roof Insulation

Do you have any other questions for us? We would appreciate hearing from you. Contact Pacific Spray Systems right away!

“Protect your home from the elements”

– Pacific Spray Systems

Spray foam insulation is recommended by Pacific Spray Systems for both new construction and upgrades to existing structures. It is especially useful for the latter purpose because, unlike traditional roll insulation, it does not require the removal of any walls or siding to install. If you’re curious about the advantages of spray foam insulation, give our team at Pacific Spray Systems a call.

Without proper insulation in your home or business, you could be losing money on heat loss, water damage and other unnecessary expenses. Turn to a foam insulation contractor to ensure that your property is fully insulated.

Pacific Spray Systems LLC is a preferred choice for spray foam insulation services in Poulsbo, Tacoma, Silverdale and Bremerton, WA. We provide our services to both homeowners and business owners. We use the highest-quality insulation to defend your property against the elements.

Contact us today to talk to a spray foam insulation contractor.


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