Safety Tips for Working with Expanding Foam

Expanding foam is a super useful part of any contractor’s toolkit. There's nothing quite like it when it comes to sealing gaps, stopping draughts and improving insulation around the edges of a building.

The flip side is that there’s nothing quite as annoying as expanding foam when it gets in the wrong places – almost everyone can speak of a clumsy first experience with the stuff!

Save yourself the hassle of a long clean-up (and throwing away your clothes) by following these simple safety tips to get the most from your expanding foam.

Check the Foam’s Expiry Date

Expanding foam relies on live chemical reactions to cause the expansion, and these reactions are most effective when the chemicals are fresh. As a result, most expanding foams have an expiry date printed on the bottom of the can.

You shouldn’t need to worry about the expiry date when buying new cans from a store, but if you’re digging out an old can from a previous job, it’s worth checking that it’s still in date. Out-of-date foams won’t expand as much and can sometimes leave a gloopy foam instead of the solid finish you’d expect.

Always Use Gloves

Expanding foam can quickly get out of hand, whether through misuse or purely because it’s usually being used in tight spaces, making application awkward. Therefore, whether it’s your first or 100th time, you need to be wearing personal protective equipment (PPE).

There are countless horror stories of people using expanding foam and then getting some on their clothes and being unable to get it out. Worse still, trying to hurriedly get rid of some with your hands – please make sure to wear safety gloves!

How to Get Expanding Foam Off Hands

Getting expanding foam on your hands is a nightmare. If this does happen to you, you have two options:

• If wet, scrub with an acetone cleaner (such as nail polish) to avoid the foam sticking to the skin.
• If dried, remove with an abrasive and/or allow to peel off over time (usually a few days).

Use a Small Amount at First

If using expanding foam for the first time, it’s easy to overestimate how much you should be spraying. While different products suggest different sizes of expansion, most expanding foams will double or triple in volume before finally setting.

Remember, if you don’t apply enough expanding foam, you can always apply more once the original attempt has set. On the other hand, if you apply too much, it won’t only make a mess but it can also cause structural issues, so it’s best to be conservative.

Use a Gun, Not the Can

Expanding foam cans come with their own nozzle attached, but this isn’t as reliable as attaching a separate expanding foam gun.

Using a foam gun comes with many advantages. First of all, it allows you to more precisely control the amount of expanding foam you release, and the longer nozzle makes it easier to reach into cracks and crevices. Secondly, guns often come fitted with seals that stop the foam from expanding inside the nozzle, a common problem when using straight from the can.

Most guns, like our Metal Expanding Foam Gun, cost less than £30 and can be reused to make all of your jobs faster, cleaner and more accurate.

Don’t Leave the Can Unattended

Because expanding foam takes a while to set, it can often go through stages of gloopiness, either where it has been aimed or on the gun or can itself. Expanding foam is almost impossible to clean off soft surfaces (like carpets), so make sure you don’t leave your foam anywhere where it could spill and cause a problem.

A good trick is to use cardboard underneath wherever you’re applying the foam and make sure you always leave the can on the cardboard when not in use.

Allow the Foam to Dry Before Cutting

Similarly, you need to allow the expanding foam to dry completely before trying to cut and prepare the surface. If you don’t, you’ll end up getting the foam on knives and other tools which can be very hard to clean.

How long expanding foam takes to dry can depend on the manufacturer and will usually be made clear on the product. Some foams will stop expanding and can be cut after an hour, but most will recommend allowing at least 24 hours for the foam to fully set before cutting, sanding or preparing.

We hope that with these tips, you’ll be able to make your next use of expanding foam a breeze.