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An easy-to-use interior sealer for effective filling of gaps and joints in wood and walls.
Features
- A professional, all-in-one interior gap sealer
- Can be used on wood, plaster, concrete, stone and brick work
- Perfect for sealing gaps around skirting boards, window and door frames
- Very good adhesion on many porous surfaces
- Stays elastic, so will not crack and fall out of filled gaps
- Forms a permanently water-repellent layer after curing
- Resistant to changing environmental conditions
- Can be painted over and contains no oil
- Acrylic-based
Brand
Drying time
24 hrs
No. of coats
1
Size
310ml
MPN
Please Select Size/Option
GTIN
Please Select Size/Option
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Overview
Overview
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Osmo Gap Sealer is a high quality, one component, flexible gap filler that has plasto-elastic qualities. It can be used for filling, fixing and repairing all manner of splits and gaps, as well as sealing and filling joints on both finished and unfinished wood flooring, skirting board and door thresholds.
Coverage is dependent on gap width and depth, but as a guide, based on 3mm gaps, a 310ml tube will fill around 30 linear metres.
- This product is compatible with the Osmo Gap Sealer Gun Applicator
- Looking for an alternative wood filler for interior use? Try Osmo Interior Wood Filler
RAL Colours
Below is a list of the corresponding approximate RAL shade for each colour:
| Product Colour | Approximate RAL Colour |
| White | RAL 9010 |
| Pine/Spruce | RAL 1001 |
| Light Oak | RAL 1002 |
| Medium Oak | RAL 8001 |
| Dark Oak | RAL 8024 |
| Red Wood | RAL 8012 |
| Walnut | RAL 8007 |
| Grey | RAL 7035 |
| Black | RAL 8022 |
Preparation
Preparation
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Surfaces must be clean and dry, removing all traces of dust and dirt before application. No primer is required for non-porous surfaces.
- Cut the dome seal of the tube with a sharp knife, taking care not to damage the thread
- Screw the nozzle on to the tube
- Cut nozzle top at angle to suite size and shape of gap to be filled
- Porous surfaces such as concrete, stone, cement and plaster can be primed with a mixture of one part acrylic sealant and 4-5 parts water
Application
Application
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Always do a test area before starting any project to assess product suitability and final finish. Follow the manufacturer's instructions on the tube at all times. For the best results, application temperature should be between: 5°C and 40°C.
- Apply Osmo Gap Sealer to gaps between joinery and other substrates of between 5mm/25mm (recommended joint depth/width ratio is 1 to 2)
- Immediately after the application, smooth the sealant at once with wet finger or a wet tool
- Excess gap sealant can be removed with a damp, lint-free cloth
- Keep the sealed joint dry for at least two hours
- Cured sealant can be removed mechanically
F.A.Q.
F.A.Q.
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Q. Can Osmo Gap Sealer be used for filling gaps between floor and skirting boards?
A. Osmo Gap Sealer is perfect for filling and sealing the gap under skirting board edges or between skirting boards and walls. It's flexible so can move with the wood, and is available in a range of colours to blend in with surrounding floor, skirting board and wall finishes. This makes it the ideal choice as a skirting board filler.
Datasheets
Reviews
Reviews
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32 customer reviews
5.0/5.0
based on last 18+ months
5 stars
27
4 stars
4
3 stars
1
2 stars
0
1 star
0
Seals welk
Having received a damaged tube Wood Finishes quickly sent another which was fine. Efficient service.
Virginia Pasquale. Pine - Spruce, 310ml (09/09/25)
Very good with no fumes
Good product with no obvious voc smell. Easy to apply
David Leah. White, 310ml (30/08/25)
We have struggled for several years with split in our kitchen worktop
Very easy to use filler. Works well. Does not contract and easy to finish.
Peter Coe. Light Oak, 310ml (19/12/24)
Easy to use
Easy to use though would have preferred a lighter shade
Fiona Wright. Light Oak, 310ml (18/11/24)
Top quality
Used this when filling a gap on a black floor nice quality like all osmo products
Adrian. Black, 310ml (22/08/24)
Easy to handle, apply and smooth when dry
Great customer service, have used it on two occasions, very satisfied with results
Mansour Seid Ahmad. Light Oak, 310ml (23/07/24)
Lasts a long time
Have previously used the light oak 3 years ago. Still usable expect the same with the dark oak. Well worth the cost.
Nick Crouch. Dark Oak, 310ml (04/07/24)
Good
It is pliable and easy to shape
Mary Holden. Light Oak, 310ml (27/04/24)
See below
Did what it said on the tin. Dressed the beam beautifully & has provided a waterproof barrier as required.
Simon Kiddle. Light Oak, 310ml (30/01/24)
Right colour for gaps in floor
Bought this to fill some gaps between wooden floors after radiators fitted. Right colour easy to use and very flexible
D Warnes. Light Oak, 310ml (01/11/23)
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