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Rafter Insulation

This insulation is fitted between the rafters of the roof. Rafter-level insulation combined with ceiling insulation can be used together where an existing attic space is converted.

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Rockwool Flexi-Slab - All Sizes


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Rafter Insulation: Features, Uses And Functions
Insulation is a great way to preserve heat in an attic or a roof space. There are many ways to install insulation, and once completed, comfort and protection within the home or office environment is guaranteed. Attic insulation are not only responsible for slowing down the movement of air, but they are also useful for sound absorption. There are simply many ways to install roof insulation, and one can do it economically as well. These insulation products help regulate the temperature and slow down the movement of air between on space to another, thus regulating the temperature of the air by the time it passes through the insulation.

Why should you insulate?

• You should insulate because you can improve your energy efficiency and reduce your heating bills.

• The environment in which you live or work will become more comfortable.

• Supports the environment by reducing greenhouse emissions.

• Can protect against unwanted noises and fire.

• It is cost effective and easy to install in most cases.

If you are building a new house or just renovating, you have to make sure that you install the correct insulation for the attic or roof. This which will help prevent the concentration and buildup of condensation with the aid of the correct ventilation. Your home can lose up-to 20-30% of heat through the roof when the insulation is not installed properly.

The most common insulation material used in this process is glass mineral fiber and semi-rigid Insulation Board. The kind of material you use will depend on the joists and rafters, the size of your attic/roof and its end use. Along with mineral wool, glasswool and rigid board insulation there are also multi-foil options available also. Multi-foil insulation is typically used along with the aforementioned insulation products, above and below the rafters. If fit correctly multi-foil insulation can create an airtight seal or close to an airtight seal to assist even greater with controlling the movement of air into and out of a building.

Installing these types of insulation between rafters is a very important process, and one must make certain that there are no gaps in between the insulation and the rafters or joists whatsoever. Any sort of gaps between the rafters or joists could result in the insulation being ineffective as gaps will cause air to rush through them. This rush of air is typically cold air from outside. When installed without gaps the insulation will control the flow and regulation of air.. Rigid foam insulation needs to be placed tightly during installation in the attic rafters so that no or very little air can leak out from within the attic space. The better the fit the more control you get over regulating air flow.

High-quality products and materials coupled with good installation will assist in providing your home or office space with a better Uvalue. U valve is a unit of measure used to measure the effectiveness of insulation within a building. Properly installed insulation with a low thermal conductivity will provide a low Uvalue.

Using Fiberglass
Using fiberglass is a very effective insulation for attic rafter insulation requirements. Now, this depends on what thickness you require and how much space you have. Using fiberglass in your attic can allow you to also deck out your attic space to create storage. In addition, sufficient ventilation is necessary for the attic to prevent mold and damp buildup. One has to make sure that there is ample ventilation opening for air to pass between the felt / roof covering and the insulation. Another option for attic spaces is PIR insulation like Kingspan, Celotex, Ecotherm, Quinntherm and Recticel insulation. All of which are rigid board insulation products and come in 1.2m x 2.4m sheets. This type of insulation is more expensive but will give you a better thermal performance than fiberglass, but more on this in another article.

Installing Acoustic Rafter insulation

To begin with the process, one must first understand by evaluating the current condition of the roof or attic. There should be no damp, gaps and air leakage in the finished process and one must make sure that all is in check and possible before the installation begins. There are many insulation solutions to choose from such as – Fiberglass, mineral wool and sheepswool. You will require different amounts of space according to the different types of thermal insulation used. So for example if you use a Knauf Combi-cut roll 200mm thick you will need to have 220mm of space available in your raters as you need a 20mm airflow. However if you do not have this space you could go with a more dense fiberglass insulation like a Knauf Frametherm Roll 35 140mm and this will give you a similar result as the 200mm roll.

Important suggestions before installation –

• Remember to hire registered contractors for the installation process.

• Find out whether the process followed by the contractor is a genuine and systematic process.

• Whether the supplier of the insulation offers installation, delivery and after sales service.

• How long is the installation process going to take?

• How many similar systems have the contractor installed before and try get references?

• What works will be needed to get the attic to its completed condition and whether the contractor will be able to provide the full service?

• Find out whether the company is certified.

How to prevent condensation

Condensation can profoundly affect your home if the attic insulation is not fit correctly. There are many factors that can lead to condensation such as – Increase in humidity, leakage in the roof and imbalance of heat. Frost can build up under your roof sheeting also due to extreme cold temperatures, and one must make sure that the rafter insulation can balance the heat flow.

Insulation4less is the UK’s largest independent online insulation store with the highest customer satisfaction ratings. We supply all the biggest and best brands of insulation direct to the end user and contractor. We supply nationwide with free delivery on all orders over £300.
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