External Wall Insulation Depth

These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

External wall insulation depth.

Our guides to building regulations in england adl1a 2013 building regulations. A u value of 0 55 w m k is used for cavity insulation and 0 30 w m k for internal or external wall insulation. Most manufacturers produce an r 13 batt that fits into a 2 by 4 wall cavity which is. An external wall insulation system or ewis is a thermally insulated protective decorative exterior cladding procedure involving the use of expanded polystyrene mineral wool polyurethane foam or phenolic foam topped off with a reinforced cement based mineral or synthetic finish and plaster.

When you are insulating two by four 2x4 and two by six 2x6 framed exterior walls and want to use fiberglass insulation what thickness is best the question becomes all more critical because of the permanent nature of wall assemblies and wall insulation. R 38 is the industry standard and the minimum thickness for r 38 is 12 inches. Measure the area needing insulation. If your current insulation is only 5 inches deep you ll need to add seven inches of insulation to achieve the 12 inch r 38 rating.

External insulation will add thickness to the wall most evident at the reveals and eaves. With that in mind when we use the word external we just mean the outside of the external walls of your house. Measure the depth of your current insulation. The thickness of thermal insulation is dependent on whatever type is required in order to create.

There are four main methods of installation the most common but not always the most effective is building a new stud wall to which insulation can be added. Standard fiberglass insulation batts or blankets provide an r value of 2 2 to 3 8 per inch of thickness. Just to be clear we only recommend insulating the external walls of your house ie. Calculate additional insulation needed.

Internal wall insulation involves the application of insulation to the interior face of external walls in order to improve the thermal performance of the property. The ones that let in air from the outside world. England new dwellings. Eaves width can be a deal breaker in that if the eaves are not wide enough to accept the insulation the cost of extending the eaves can outweigh the benefit of the insulation.

For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed your attic to reach r 30 if you live in zones 2 or 3. Once the insulation is in the wall and sealed up with drywall it is not easy to change out.