Flat Roof Insulation

Flat roof insulation is crucial for improving the energy efficiency, comfort and living standards in buildings.

Reference case, Taulov Dry Port, Hardrock, building site, FRI, roof, construction

Why do we need flat roof insulation?

Most thermal transmission is usually through the roofing area. Flat roof insulation is an essential tool that can enhance the energy efficiency of a building and reduce fuel costs.

Creating more effective flat roof barriers also offers your building further protection from the unpredictable outdoor climate, including overheating in warmer days, rain and storm.

From high rise apartment blocks, to residential designs, industrial units, large commercial facilities and schools or hospitals, flat roofs are an integral part of modern building design.

Constructions such as terraces, rooftop gardens, blue roofing with water retention and roof spaces which are used for solar purposes are becoming ever more popular. This growing trend for functional roof spaces brings even more demand for effective insulation, helping to enrich the space available on top of your building.

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Flat Roof Insulation Products

Flat Roofing Solutions

HardRock® Multi-Fix (DD)

HardRock® Multi-Fix (DD) is a BBA-approved insulation board, that in addition to thermal comfort, provides independently-tested acoustic and fire resistance properties.

Flat Roof Solutions

HardRock® Multi-Fix Recovery Board

Maintaining roof surfaces is crucial for the protection of property, both in commercial and domestic settings. Specifically developed for use on flat roof refurbishment projects, HardRock® Multi-Fix Recovery Board is a non-combustible board compatible with all commonly used flat roof membranes, including single-ply, EPDM, bitumen and liquid-applied systems.

Flat Roof Solutions

HardRock® Multi-Fix (DD) Tapered

Non-combustible tapered insulation for flat roofs. HardRock® Multi-Fix (DD) Tapered is a BBA-approved insulation board, fabricated to a fall to provide drainage across a roof.

Applications

Insulation

Steel Deck Insulation

Enhance your building with ROCKWOOL steel deck insulation. Durable and fire-resistant, our insulation is designed to be energy efficient and long-lasting.

ROCKWOOL Consolidation

Insulation

Concrete Deck Insulation

Installing concrete deck insulation can significantly reduce your energy costs. Discover the benefits of ROCKWOOL concrete flat roof insulation today.

ROCKWOOL Consolidation

Insulation

Warm Roof Insulation

Achieve maximum thermal performance with ROCKWOOL warm roof insulation. Made from stone wool, it’s designed to last the lifetime of your building.

ROCKWOOL Consolidation

Installation

When installing there are a few key things to bear in mind:

Key tips:

Take accurate measurements of the area you are insulating before getting started
Always lay the insulation in dry weather conditions
Remove loose debris from the existing roof surface
Lay the boards tightly with staggered joints

Inspiration and guides for professionals

Calculator and savings

Roof insulation is very cost-competitive when saving energy consumption overall – and provides a key, valuable investment for the future.

In addition to this, flat roof insulation often has a relatively fast payback time in terms of money, energy, and carbon footprint.¹

There is no ‘one size fits all’ answer to how much flat roof insulation you’ll require. Since there is usually no limitation to the installation height on a roof, and ‘the sky is the limit’ so to speak, insulation thickness can be adjusted to almost any possible customer specification and local regulatory energy demand.

The average installed density of stone wool insulation in South East Asia is around 90 – 160 Kg/m3.

Use our ROCKWOOL U-value calculator to determine the thermal performance of the building's roofs and possible cost savings. For more details on technical specifications, visit our ROCKSPEC Specification Toolkit.

Learn about energy efficiency

ROCKWOOL solutions for flat roofs are durable and proven by more than 40 years of use. ROCKWOOL flat roof insulation is also non-combustible and will protect you, your building and inventory if a fire occurs.

Kim Brandt

Kim Brandt, Global Product Manager, ROCKWOOL

FAQs

How thick should flat roof insulation be?

Do you need to ventilate a warm flat roof?

What is a cold flat roof?

Case studies

The project

Wilmcote House in Portsmouth, UK, is a high rise, high density housing estate built by local authorities in the 1960s.

The aim of the project was to create an improved environment to benefit the health and wellbeing of residents, providing comfortable, safe and thermally efficient homes for many years to come.

The problem

Residents were not using their electric heating, as it was too expensive.

This was leading to issues with mould, damp and condensation, causing poor living conditions.

The solution

A huge retrofit of Wilmcote House was carried out, using a combination of several products and systems.

This included a ROCKPANEL cladding façade system, and a combination of ROCKWOOL external wall and flat roof insulation, together with a selection of our fire protection products.

Read more about Wilmcote House

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