In an effort to reduce energy bills and, more recently, carbon emissions, many homeowners have been using various forms of insulation as draught proofing and to reduce heat loss.

One of these is Spray Polyurethane Foam (SPF) which can be applied to roof spaces, walls and floors. Applied by spray gun, it’s relatively easy to use when working with unusual designs and tight spaces where a custom application is necessary for safety or to minimise disruption.

For these reasons spray foam has become a popular form of insulation that’s often marketed as an easy and simple fix, when in fact the installation of spray foam should be seen as a significant and fundamental modification to a property that can have an impact on valuation, home surveys and lender decisions, and for these reasons needs careful consideration and planning.

What’s more, Trading Standards and various media reports have highlighted issues with ‘cold-calls’ or unsolicited offers to sell or remove spray foam installations from properties.

The newly issued RICS Spray Foam Insulation Guide. 

To address the pros and cons surrounding the use of spray foam, RICS has issued a guide to provide consumers with clarity in these areas, and to inform the homeowner on the ways in which spray foam insulation could impact a property.

RICS is the largest organisation for professionals working in property, land and

construction worldwide. Information in the guide covers topics such as what effects spray foam might have on a property’s roof structure, thermal performance and value, do’s and don’ts when installing insulation to your home, and how RICS-accredited members can help assess your property.

(The RICS guide doesn’t apply to new build structures where spray foam

insulation was included when the homes were built, or loft conversions where new insulation was designed and installed to be compatible with the conversion from loft void to a liveable room.)  

A few of the Guide’s main pointers to consider before installing spray foam insulation:

  • If considering spray foam insulation, do not accept ‘cold-call’ or unsolicited offers of spray foam installation.
  • Do not install spray foam insulation in a listed or other protected building without prior consent.
  • Do not carry out isolated alterations without careful due diligence and planning.
  • Get advice from an independent, impartial professional if you are considering alterations or modifications at your property (someone who does not have a commercial interest in selling you their product).
  • Look after and maintain your property in good repair, keeping it wind and watertight.
  • Consider the whole property before carrying out any alterations.
  • Consider how your property is designed to perform – specifically, understand where ventilation is needed in your property.
  • Consider where you live in the building and consider installing more insulation next to your living spaces, for example, at ceiling level in the loft to keep the heat near the rooms you live in.
  • Check with your mortgage provider whether their lender policy allows the installation of such products.
  • Check with your insurance provider whether their policy allows the installation of such products with potential increased fire risk.
  • The RICS Guide covers many of the important aspects of spray foam for anyone considering the application of this form of insulation.

Some common insulation alternatives to spray foam.  

Insulation batts. More flexible than insulation boards and no problem on an uneven surface. Also provide better acoustic insulation and often used for roof insulation. Applications: Glass wool: insulation inside (pitched roofs, interior walls). Rock wool: ecological alternative to glass wool. Wood wool: walls and roofs.

Insulation boards. One of the most frequently used forms of thermal insulation. With a high UV coefficient and easy to install. Applications: PUR (polyurethane): floors, roofs and cavity walls. PIR: floors, roofs and cavity walls. EPS (expanded polystyrene): floors, walls and roofs. XPS (extruded polystyrene): basements, overlay roofs, roof sarking, facades and cavity walls

Blow-in insulation. Similar to spray insulation but more environmentally friendly. Suitable for insulating hollow spaces and places that are difficult to reach, like cavity walls or attic floors. Glass wool or cellulose flakes can be blown in.

Insulation Roll. An eco-friendly alternative to traditional glass wool insulation. Recycled plastic insulation is comfortable to work with, easy to lay and comes in handy sized rolls to fit many existing rafter spaces. Easily inserted into a variety of cavity spaces. Made from recycled plastic bottles, and breathable.

Glass mineral wool. Lightweight and energy saving loft insulation, commonly laid for the effective thermal insulation of pitched roofs at ceiling level as well as suspended timber floors. Consists of a flexible, lightweight low-density glass mineral wool quilt. 

To find out more see the RICS insulation guide here.