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Frequently Asked Questions

Frequently asked questions that we receive about CorkSol, SprayCork, and Approved Applicators

Does SprayCork have a smooth finish?

No, it is a textured finish. It’s slightly stippled, and it is the granulation of the cork which gives it its performance.

Can I go over my existing render?

Yes, it is possible to go over existing renders and other substrates and still get a 25-year product warranty. However, just to manage expectations, SprayCork will not hold your wall together so any blown or shot render will need to be rectified first. For example, if you have sand and cement render which is painted and has hairline or settlement cracks, as long as the substrate is solid you can go direct onto the render. The best thing to do is get an Approved Applicator to do a site survey and they will be able to advise you.

Can it be sprayed directly onto pebble dash or roughcast?

Yes, absolutely. SprayCork will go directly onto pebble dash, roughcast, dry dash, wet dash or stippled paint. Please note the overall thickness of SprayCork is around 6mm so the texture of the dash will still be visible. However, the finish will look more subtle and is very effective. If a smoother finish is required, a base coat will be needed first. Please speak to an Approved Applicator or our in-house technical team if you're unsure.

Can CorkSol be applied direct to brick?

Yes, SprayCork will stick to any substrate (apart from silicone), including brickwork. As the overall thickness is around 3-4mm you will still see the mortar lines of the bricks. If you want a smoother finish a base coat will need to be applied before spraying the cork. Either finish looks effective so it is purely personal choice and/or budget. If the bricks are dusty a primer may be needed but the Approved Applicator will advise on this. If any pointing is missing this will need to be repaired prior to spraying.

Does GMS apply the spray?

GMS does not apply the product. We sell the product to a network of independent companies who have completed and passed training at our purpose-built training centre to become Approved Applicators. They are Approved Applicators. You will need to contact a local Approved Applicator for a quote. Please contact us for details of companies local to you.

How much does SprayCork cost?

GMS Insulations does not get involved in pricing of the work. We leave that entirely up to the Approved Applicators. Each job is different due to access, size and condition of the building, location etc so the Approved Applicator will need to conduct a site survey to quote. On very rare occasions, it may be possible for them to give a guide price based on photos. If you're unsure if your job is suitable for cork or would like some technical guidance, call us and ask for the technical team. They’ll be able to discuss the product with you, explain the work involved and confirm if the job is suitable for SprayCork when they’ve been able to study the photos. The photos can be emailed to prior to your call.

What is the U-Value of Spray Cork?

This is probably the most asked technical question. We don’t give a U-Value for the product on its own as that is determined by the complete build of the wall. If you wish to calculate the U-Value of your wall, SprayCork’s Lambda value is 0.058W/mk. We have test results which demonstrate the potential reduction in the U-Value, and these may be viewed in the blog section of our website. As SprayCork is one continuous skin with no joins or gaps, it improves air tightness of the walls which isn’t measured in U-Value testing.

How do I find an Approved Applicator?

Either search online or contact GMS Insulations directly. We will take some details from you and contact local Approved Applicators to ask them to get in touch with you. We do ask for various details from you but these are used purely to get a suitable local Approved Applicator in touch with you. Alternatively, please fill out the contact form by clicking on the Find an Approved Applicator button at the top of the page.

How many colours does SprayCork have to choose from?

We have a standard colour range with 28 fade resistant colours. We also have a colour pigment machine in house which can make up to 1800 colours so if you have a specific RAL code we can make this colour (min order required 300m2 or development cost on smaller orders) for any commercial property orders.

My property is on the coast. How does SprayCork protect from sea salts?

Cork has evolved over millions of years in coastal areas of the Mediterranean and has become naturally resistant to sea salts. SprayCork is resistant to sea salts and algae. We have some case studies on this topic in our blog section on the website. If your property is on the coast be aware your house/building will need to be specially washed and treated before application. This will be included in the quote from the Approved Applicator.

Can i jet wash the product? How do I maintain SprayCork?

Yes, you can jet wash the cork but don’t get too close. If the pressure is too high, it will damage the cork (pressured water is a very effective blade!). Cork has anti-microbial properties and naturally resists against algae but an annual clean is recommended.

Does GMS Insulations offer a warranty?

The warranty is provided by the manufacturer and relates to the product only. You will need to speak to the Approved Applicator regarding a warranty on their workmanship. The product warranty is for 25 years. The warranty covers any issues with the product failing. It excludes damage caused to the product after installation or poor workmanship.

How do I get a sample to look at?

The easiest and fastest way to get a sample delivered is to call us direct at 087 2394962 and request a sample in a colour of your choice. The colour range is available here - If you have requested a quote, the Approved Applicator will have colour swatches and colour charts when they visit the property.

Can SprayCork be painted over?

SprayCork can be painted although this shouldn’t be necessary as it is long lasting and available in a range of colours. Care should be taken to use a paint which is breathable and as natural as possible to avoid making the warranty invalid. Painting may affect the breathability or fire resistance of the product, so we do not recommend it.

Is SprayCork a better insulator on the inside or outside of my house?

This is a great question and one to definitely consider when upgrading your property. SprayCork can be sprayed internally then skimmed/plastered over to create TIWI (Thin Internal Wall Insulation) at only 8mm including smooth finish and paint. Alternately SprayCork can applied externally on your home/building to refresh and dramatically improve the appearance, as well as offering a multitude of benefits. Either option gives flexibility, breathability, thermal and acoustic insulation, mould and condensation elimination and fire resistance. The performance remains the same. Both options have been tested to ISO9869 and offer around 30% energy savings on heat transfer through walls. Internal application is advisable for dealing with condensation or black spot mould and is particularly useful in heritage buildings or areas where external application isn’t possible.

Can anyone book on an Approved Applicator course?

No, this is a specialist coating designed for trade use and is not a DIY product. We always qualify companies who want to book on the course and applicators are fully trained and from a suitable trade. If you are interested in becoming an approved applicator please contact us at or 049 4335057087 2394962

What is the application process?

The application process is the same for internal and external applications. As long as you have a clean dry surface the SprayCork will adhere to any substrate except pure silicon. The product is a sprayed application either sprayed by a gravity fed hopper gun or a spray machine which can spray with a 6mm nozzle (airless does not work). Two coats need to be sprayed to build the product up to a thickness 3-4mm. For internal works the SprayCork can be skimmed/plastered directly onto with no primer/PVA please note drying times are significantly slower and Multi-finish, Board-finish and airless plasterers all work.

If you have any more questions please contact us through either

Phone – +353 87 2394962
Email –