how to fix insulation for flat roof

how to fix insulation for flat roof

Fixing insulation for flat roofs have evolved over the years to where we are today. The new thermally broken fixings for warm flat roofs we now prefer to use. Mechanically fixing down the insulation to a flat roof is the preferred method.

What insulation is best for a flat roof?


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

Putting insulation for flat roof:



Can you put insulation in a flat/directly on the roof?

A flat roof, whether it covers the entire structure or is part of an addition, can be thermally insulated to reduce heat loss. When insulating a flat roof, you have two choices: a cold roof or a warm roof. These flat roofs can then be waterproofed with a variety of membranes.

Is it possible to install insulation directly on the roof? Generally, experts advise builders not to put fiberglass insulation directly on the underside of roof sheathing.

Where do you put insulation in a flat roof?

Insulating materials are therefore installed between your ceiling and the roof membrane in insulated flat roofs to prevent heat from leaving or entering your property.

How thick should flat roof insulation be?

What Thickness Insulation Do I Need for Flat Roofs? A flat roof with no insulation has a U-Value of about 1.5 W/m2K. When insulating one, you want to achieve a value of 0.25 W/m2K or less. To accomplish this, insulate your flat roof with insulation boards totaling roughly 150mm in thickness.


Insulation on the roof /flat roof:



What can I use for a vapor barrier on a flat roof?

Damplas Vapour Control Layer (VCL) is designed for use in Flat Roof constructions to minimize moisture intrusion into structure surfaces and increase building airtightness. The VCL also helps to increase building insulation by limiting the circulation of warm damp air.

Can you insulate between joists on a flat roof?

To meet building codes, cold flat roofs must be insulated between joists or between and below joists. A ventilation cavity should be left between the insulation and the waterproofing layer.

How do you insulation a flat roof with no attic?

Spray insulation is arguably the easiest type of insulation to install on a roof without an attic. The foam can be sprayed into the gaps and crevices of a wall. Ceilings can also be sprayed with batts and reflective foam insulation. The foam will solidify into a strong insulating substance once applied.

Is it better to insulate the roof from inside or outside?

Flat roofs are most insulated on the outside, preventing heat loss and lowering energy use. You can avoid moisture damage in the wooden construction by placing insulating material on top of the roof structure. This risk is increased for flat roofs with inside insulation.

Can I use polystyrene for flat roof insulation?

EPS is a popular insulation material because of its flexibility and thermal performance. The boards can accept a variety of flat roof waterproofing systems and can be simply cut to many different shapes, sizes, and falls as needed.


I hope this article was helpful to you. But what’s more helpful is professional roofing service at your beck and call.

LeakStop is a one-stop destination to meet your roofing-related requirements. We offer roof repair, replacement, maintenance and inspection services all over GVRD (Greater Vancouver Regional District).

We offer a free inspection to first-time clients. Connect with us TODAY at 1 866 777 0084 for immediate assistance!

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Derek Lindsay

Derek has been a part of the Roofing Industry for 20+ years. His experience in the field enables him to write insightful and informative content on Roofing and everything related to Roofing.