Things to consider before buying or using expandable foam

The expanding foam is a product usually used to insulate and seal cracks in the walls by conforming to the surface where it is applied. It is mainly used around windows and door installations to fill the gaps. Also known as insulation foam, it works as temperature insulation (preventing the cold or hot hair from leaving/entering the room) or a barrier for sound (sound-proofing applications).

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Because this foam filler can fit into any space, applied with a straw applicator, can be used for sealing holes and cracks around the home or commercial buildings, from their foundation to the attic.

There are two different types of expanding foam :

Spray foam (Spray Polyurethane Foam – SPF)
Low expandable foam in a can

The spray foam is a chemical product created by mixing two liquids (two separate chemical compounds) that react when combined and heated and expand their liquid volume multiple times. This type of insulation is used for commercial and residential buildings, for large areas, being custom-fit to any construction material or architectural design.

Types of spray foam

HIGH-DENSITY	MEDIUM-DENSITY	LOW-DENSITY
3 lbs./cubic ft., closed-cell foam	2 lbs./cubic ft., closed-cell foam	0.5 lbs./cubic ft., open-cell foam
R-Values start at 5.5 per inch	R-Values start at 5.7 per inch	R-Values start at 3.6 per inch
For exterior and roofing applications	For continuous insulation, unvented attic applications, interior wall cavity fill	For interior wall cavity fill and unvented attic applications

The higher the R value (*R indicates resistance to heat flow), the greater the insulating power.

Where or when you can not use expanding foam

Based on the type used and the person who applies it but also because it is a chemical product in liquid form (when the application begins), there are several situations when the use of foam is not recommended:

spaces that are too close to electrical boxes: When you need to fill the space between an electrical box and the wall, there is a risk to get foam inside the box and jam up the components. Moreover, you will introduce flammable chemicals to your electrical box. For this area, you should use a low-expanding foam.
areas too close to ceiling lightboxes
closed-cavity locations
open-cell spray foam on the roof: You should choose the closed-cell spray foam for the roof insulation.
if you know that you have a history of respiratory, asthma, or skin problems

Low Expanding Insulating Foam

This type of foam (manufactured by Fix46 Supplier – an independent European manufacturer) differs from the spray foam as it is a one-component polyurethane product that hardens due to air humidity.

Inside the can, it is present just one chemical compound that strongly reacts with water and other substances containing an active hydrogen atom. The foam is manufactured in compliance with the requirements of ISO 9001:2008 standard.

Can be used for:

Cracks
Gaps
Filling free spaces
Sealing for door fitting
Sealing for windows fitting
Pipe penetrations
Thermal insulation
Acoustic insulation
Sealing roofs, walls, and floors

The foam presents ideal adhesion to typical construction materials such as concrete, bricks, wood, plasterwork, metals, hard PCV, Styrofoam, and rigid PUR. The working surfaces need to be cleaned and degreased, and it is recommended a sprinkle with water.

How to apply the low expanding foam

For the best results, the optimal room temperature should be in the range +5°C to +30°C and the can temperature in +10°C to +30°C. The foam should be used in spaces with fresh air and good ventilation, avoiding application in direct sunlight. Make sure the working area is clean and free from dust. As the air humidity helps in hardening, the manufacturer recommends spraying some water on the surfaces where the foam will be applied.

During the whole application process, use protective gloves to avoid skin contact. Keeping the can with the valve facing down, shake it vigorously for 10-20 seconds.

Screw the can onto the gun applicator and always use the can upside down. Keep in mind that the foam will increase in volume so do not fill the entire gap.

If the application is suspended for more than 5 minutes, please clean the applicator nozzle using polyurethane foam cleaner. When you restart working, shake the can again before application.

How to remove expandable foam

Now that the job is finished, you are bound to find some residues on the surfaces surrounding the treated portion of the wall: on the floor, clothing, hands, or uncovered skin.

The cleaning bit can prove quite a challenge sometimes, depending on the area affected. However, there are several products designed to help you deal with this issue:

To remove low expanding foam from the hands, you can use specially designed wet wipes (Gorilla wipes, for example). These wipes contain cleaning agents that will remove the foam without leaving any traces in a matter of seconds.

Another way of cleaning the foam from the skin is by wiping off the excess foam using a cotton cloth or a paper towel, followed by applying vaseline or a bit of olive oil to remove the remaining gum-like layer. Soap and water will then finish off the skin cleansing.

Cleaning the expanding foam from surfaces like walls, wood, and plastic can be done using wet wipes designed to remove the expandable foam or silicone-based fillers.

Another cleaning alternative is using a solvent suitable for the surfaces treated – soft or hard materials. Sometimes, the foam manufacturer adds information about removal from undesired areas on the How to use list.