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Using Great Stuff Foam On Gaps & Cracks [The Best Gap Filling Ideas!]

You can work with those gaps in your window areas when you are sitting idle.

Do not also leave behind the surrounding door areas.

This is when you have the Great Stuff products at your disposal.

I shall help you with using Great Stuff foam for gaps and cracks.

The process starts by preparing yourself with eye-wear glasses and gloves. Hold the can firmly to pull the trigger, which would spray the foam in the gaps. By allowing some time for the foam to dry, you will trim the solid foam next. In the end, you will clean the area for a fresh look.

Take some time to read this article to do the job efficiently!

Filling Small Or Big Gaps Using Spray Foam

The “Great Stuff” is the product name that holds spray foam inside a can. The easy-to-use products can be used to fill tiny or large gaps. There are different products for filling small and extensive gaps.

While knowing how to use Great Stuff foam for gaps and cracks, you should take notes. Some products are used to fill 1-inch gaps.

There are also great stuff products that can be used for filling significant gaps. This is larger than 1-inch. In addition, there are separate great stuff products for pest control.

You are going to be learning how to reuse great stuff in gaps and cracks. This is in the areas around windows and door gaps inside your house.

Step 1: Prepare Yourself

The first thing to do is to acquire all the products suggested above. You may or may not buy the pest control product. This is depending on if there are pest issues or not.

The excellent stuff product generates the best-expanding foam for significant gaps. You must handle them with care for safety reasons. You can apply them for a perfect baseboard big gap filling.

In the first step, you need to prepare yourself. This should be done by having an accurate idea of what you are about to do. Make sure you shake the cans for about a minute or so.

You also need to have some protective gear with you. You must have eyewear glasses. This is to prevent the thin foam spray from getting into your eyes.

In addition, I won’t stress enough the importance of wearing gloves. This is to keep your hands clean. But most importantly, it allows you to explore the gaps in your windows and doors.

Step 2: Pull The Can Trigger To Spray

Once you have shaken the cans, they are ready to be sprayed around. Inspect the can trigger a little. You would notice they are evenly fixed to the can.

You are given some suggestions in the instructions area at the back of the can. One of those is not to pull the trigger too firmly or strongly. You may break the outlining if you do so.

Before pulling the can trigger, read all the instructions properly. This is to understand how to use Great Stuff windows and doors. The usage of a big gap-filling can is probably different from a small gap-filling can.

With the big gap filler, the volume of foam comes out densely. This is why you should properly grip the can while applying. You don’t want to make the whole area messy.

Start with filling the small gap areas. Make sure you slowly pull the trigger to let the foam come out. Squeeze the trigger gently to foam the gap from top to down.

You have now understood how to use Great Stuff big gap filler. To have a better grip, spray the more giant gaps with the suggested indications.

Step 3: Allow The Foam To Settle And Dry

As you have spray foamed all over the different gaps, see the foam action. In the most fluid form, the foam drips down a bit. It will dry and settle into the wooden surfaces as it moves around.

Putting caulking on the window or door edges is usually not recommended. The process is similar to patching up hollow holes on doors.

Make sure you fill up the cracks that are there on the beams of the woodwork. The minor gap fillers would do the job sufficiently.

You can compare Great Stuff big gap filler vs regular. The big gap-filling foam would expand more comprehensive than the regular ones.

This is why being careful with the foam is good to avoid hassles. This is while trimming the over-layered dry foam.  The usual question would be, what causes the foam to expand?

The diisocyanate contents of the foam work with some fluid to cause a polymerization reaction. By producing carbon dioxide gas, the response would decompose. This makes the foam solution expand while hardening at the same time. The answer is designed to create a cotton-like foamy structure.

You can ultimately allow up to one hour for the foam to settle in. A complete hardening will make the expanding foam stretch out. You have a few things to do to even out the foam lining.

Step 4: Trim The Dried Foam

When you are done with the Great Stuff spray foaming, store the cans safely. Read the instructions to know at what temperature they should be stored.

As you are done exploring, Great Stuff big gap filler dry time, the wait is over! You will need a knife to cut around the excess rigid foam.

Consider the attempts to trim large door gap fillers. The process is way less complicated than this. You are going to cut down the solid formation of the foam.

The big gap filler foam will stop expanding after a specific time. This is when the foam is entirely settled in between the woods. Cutting the foam won’t do the job; you must trim it.

The use of a box knife can help the trimming process. It will nicely even the foam linings in between the gaps.

Step 5: Clean The Area

After the trimming is complete, there will be residues all over the place. You can remove all the waste by wiping the area. The use of a dusting cloth can be recommended to remove any dirt.

You may wonder if Great Stuff gaps and cracks are waterproof. The answer is yes, they are. You won’t have any problem applying a wet or dampened sponge to it.

Use the flammable spirits to consider a deep cleaning process. The use of baking soda cannot be overruled as, well. You would also have the option of filling up the gaps with cement coverings.

In this case, you have to spray paint the area. This is to make the entire space look new and fresh.

Tips For A Long-Lasting Spray Foam Solution

You have probably worked hard in all the steps. This means you would want your work to last long. You can apply some hacks to mastering the art of spray foaming solution.

Here are a few things you can do to make your woodwork look new and fresh. This is for an extended period!

  • Application of white vinegar regularly to make the surface look fresh and smooth.
  • Apply wood wax to any new appearing small gaps before adding fillers.
  • Some kinds of oil can also be used to ensure a shiny look.
  • Pain the surfaces with varieties of colors for smooth finishes.
  • Get rid of stains by cleaning with baking soda.
  • Apply a sanding process to any cracked area.
  • This should be followed by some spray paint as well.

The best-looking exterior comes as a result of passion. You should be passionate enough to do the job all by yourself.

Here are a few things to purchase to complete the job:

Great Stuff 99112809Smart dispenser pest block
Great Stuff 157911Insulating foam sealant
Great Stuff 343087Strong bonding adhesive
Big Gap Filler Insulating FoamFills gaps more significant than 1-inch
Great Stuff 343087 PROMoisture-cured foam adhesive


In what areas should I not use expanding spray foam?

You should not use expanding spray foam in areas closer to electrical boxes. You should also avoid spraying the foam on ceiling light boxes.

What should I do to make the great stuff spray foam cure properly?

To cure faster, you can open the windows to let air come in. Being exposed to atmospheric moisture, the foam would cure properly. Also, the cure may happen faster than the suggested 8 hours.

What is the difference between a sealant and a filler?

In the longevity department, the sealant lasts for about a year. On the other hand, the fillers can last for ten years. The sealant is done as a preventive measure where the filling is done to fix. 


Knowing about using Great Stuff foam for gaps and cracks will make you an expert. With this knowledge, you can help your friend and family around.

I hope you do well in your quest.

Wishing you all the best, I am off! Adios!