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Gap Filling Adhesive

(Last Updated On: 2 June 2023)

Gap Filling Adhesive

When there’s a gap between two materials that need to be joined together, a gap filling adhesive is essential. Adiseal, a high-performance adhesive and sealant, excels in filling gaps with its impressive properties. This adhesive not only creates a strong bond with high gap fill, but also retains flexibility, waterproofing ability, and is solvent free. Additionally, we’ll explore the options for best gap filling adhesive in this article.

Why is a gap filling adhesive a better option than a regular adhesive in certain applications?

When attempting to adhere two items together, it is common for the surfaces to be uneven or irregular. As a result, when the items are joined together, certain areas will make contact while other areas will remain separated by a gap. This is especially true for materials with uneven or non-flat surfaces, which can make it difficult to achieve a secure and lasting bond.

When using a glue or adhesive with low gap fill, the resulting bond will only be effective where the two surfaces are in close proximity. However, if there are gaps between the surfaces, the adhesive will not be able to sufficiently fill the space, leading to a weaker bond. Adiseal, a high-performance adhesive and sealant, offers superior gap filling properties to ensure a strong and durable bond. In contrast, other adhesives may even fail to reach certain areas, leaving holes and ultimately resulting in a lack of adhesion.

Best gap filling adhesive

Adiseal has undergone an independent test conducted by Ultimate Handyman to determine its adhesive strength, and the results were remarkable. In the test, which involved assessing the bond strength between wood and metal, Adiseal proved to be the strongest adhesive available also determining it’s performance as a grab filling gap adhesive. In fact, nothing else came close to the exceptional performance of Adiseal. To see the test results for yourself, check out the video below.

Best gap filling adhesive. Strongest in test.

Construction adhesive strength test

Ultimate Handyman conducted various tests to determine the strongest construction adhesive in the market. One of the tests involved measuring the pressure required to break the bond between wood to metal. To accomplish this, the following steps were taken:

  1. The metal sheet was thoroughly cleaned.
  2. Each construction adhesive from different manufacturers was applied to a piece of hardwood.
  3. The wood was firmly pressed onto the metal.
  4. The adhesives were allowed to cure.
  5. A hydraulic ram was used to break each adhesive bond.
  6. The pressure at which each bond broke was measured.


The best grab adhesive was Adiseal

In the independent tests carried out by Ultimate Handyman, Adiseal proved to be the undisputed winner and the best grab adhesive available in the market. The test measured the strength of the adhesive bond between metal to wood, and Adiseal outperformed all other adhesives tested by a staggering margin – over three times stronger than the next best product. The test had to be abandoned when the screws holding the metal sheet down started to rip out, and the hydraulic ram seal broke, causing fluid to leak out. The exceptional strength of Adiseal was too much for the testing rig to handle.


ProductMaximum pressure at which the adhesive bond broke (measured in pounds per square inch, or psi)
Tec 71016
Loctite PL Premium873
Gorilla Grab Adhesive862
Bond It PU18582
Bond It Save Nails411
Strongest adhesive test results
Adhesive strength test by Ultimate Handyman. Adiseal gap filling adhesive was way stronger than anything else.

“That is actually unbelievable!”

Ultimate Handyman



Testimonials & some comments on the: Grab adhesive tests 2017, video on YouTube

  • That Adiseal is phenomenal!
  • That Adiseal is some stuff though, definitely need to get some of that bought!
  • I instantly went looking for Adiseal!
  • Need to get my hands on some of that to try out.
  • Looks like a cracking product.
  • Having used the two most expensive brands on numerous occasions, I’ll be trying out the others, especially the Adiseal.
  • Adiseal certainly surprised me in this test!
  • Fantastic tests. It’s unbelievable that Adiseal test with the hardwood.



Solvent free gap filling adhesive

When it comes to adhesives, solvents can cause a host of problems. Cheaper adhesives often contain solvents, as they are less expensive to manufacture. However, solvents can cause issues with gap fill. Solvent-based adhesives cure as the solvent evaporates, leaving less active product in the cartridge. As the adhesive shrinks during curing, it may pull away from the material it is adhered to, resulting in a weaker bond and less gap fill.

Adiseal, on the other hand, is a solvent-free adhesive and sealant that does not shrink once applied. This high-performance adhesive provides excellent gap filling properties and creates a strong, flexible, waterproof bond. In contrast to solvent-based mastic adhesives, Adiseal offers superior performance and durability. Check out the video below to see for yourself how Adiseal compares to solvent-based adhesives.

Video of mastic adhesive shrinking as solvent evaporates away.

Adiseal construction adhesive is a versatile and high-performance product that can successfully bond a wide variety of materials, including:




Applications & Benefits

Adiseal is a versatile heavy duty construction adhesive that can bond and seal a wide range of materials including metals, wood, glass, mirrors, concrete, masonry, stone, tiles, polystyrene, roof felt, fibreglass, most plastics, and many other items. In addition to its bonding capabilities, Adiseal can also seal a variety of applications such as baths, showers, gutters, drains, sinks, vehicles, boats, felt roofs, and many others.

Many benefits of Adiseal include:

Adiseal is the ideal solution for professionals and DIY enthusiasts looking for a reliable adhesive and sealant that can handle a wide range of applications.


Adiseal is available in the following colours:


Gap filling grab adhesive

Adiseal adhesive & sealant is a high-performance, gap filling grab adhesive that creates a strong bond with impressive properties. For even higher grab, you can use Adiseal Hi-Grab gap filling grab adhesive, which is designed to be very thick, providing even higher gap fill and grab properties. However, due to its thickness, a good quality sealant gun (caulking gun) is required to extract the product from the cartridge. With Adiseal Hi-Grab even larger gaps can be filled.

Gap filling glue

Adiglue is a high-performance gel glue that excels in gap filling. Its thick gel formulation allows it to remain in place while drying, resulting in higher gap fill properties than traditional liquid glues. Unlike solvent-based products, Adiglue is solvent-free, so it does not shrink during the curing process. To speed up the drying process and seal porous materials, Adiglue activator can also be used.

High gap fill glue. Gel formulation for higher gap fill.
Gap filling glue

The following video demonstrates the thicker gel formulation of Adiglue, which enables it to remain in place in gaps while it dries.

Video demonstration of gap fill glue with thicker gel formulation.

Frequently asked questions about gap filling adhesive

What is the best gap filling adhesive?

Adiseal was found to be the strongest construction adhesive on the market, outperforming all other products tested. Adiseal is solvent free, ensuring that it doesn’t shrink or crack over time. Its flexible and waterproof properties make it ideal for a wide range of applications.

Where to buy gap filling adhesive?

In the UK, Adiseal can be purchased from stockists. For other countries Adiseal products can also be purchased from https://guglue.com

What is gap filling adhesive?

A gap filling adhesive is an adhesive that can fill a high gap between items that need sticking together. It will remain in place in the gap whilst it dries instead of running down.

How to store Adiseal gap filling adhesive once it’s been opened?

Once a cartridge of Adiseal has been opened, leave about 1cm worth of product out of the nozzle. This part will cure and create a cap. Store the Adiseal cartridge in a dry place. Adiseal should still be OK to use for a good few months if stored in good conditions. If the the product has cured further down the nozzle then either cut or replace the nozzle.

Suhail Matadar has extensive experience in the construction industry as an electrician, involved in installing, inspecting, and testing electrical systems in various projects. He excelled in sales, working for a major UK wholesaler, selling construction products to professionals and the DIY market. Suhail's background includes working at a leading home emergency repair company dealing with trades people. With a BEng (Hons) degree in Electronic Engineering, Suhail has worked with PLCs in the nuclear fuel manufacturing industry. During his studies, he gained practical experience at a chemical manufacturing company known for producing award-winning cleaning, hygiene, and livestock protection products for over a century. Currently, Suhail runs a global business specialising in supplying, researching, testing, and distributing chemical construction products like adhesives and sealants.