Focus on floors: your questions answered

We've picked some of the most frequently-asked questions from the hundreds answered by F. Ball’s technical team in the past few weeks.

Q. I’ve installed LVTs in a new conservatory. After less than a year, the floor has failed. The adhesive appears damp. What could have caused this?

A. This is very likely a result of residual construction moisture. Where subfloor relative humidity (RH) levels are above 75% (65% where wood floorcoverings will be installed), a waterproof surface membrane should be installed to stop excess subfloor moisture rising up to the level of floorcoverings and potentially causing complete floor failure. In this instance, you’ll have to remove the LVTs and mechanically prepare and clean the subfloor. Where subfloor relative humidity levels are below 98%, you can use Stopgap F77 to create an effective barrier against rising damp and residual construction moisture. You can then proceed to using a levelling compound to create a smooth base ready for the receipt of LVTs. It’s recommended that a temperature tolerant adhesive, such as F. Ball’s Styccobond F49 Hybrid PS, is used to install LVTs in a conservatory, to stop the movement of floorcoverings caused by extreme temperature fluctuations as a result of solar gain.

Q. What adhesive is recommended for installing rubber floorcoverings over chipboard?

A. Styccobond F58 acrylic emulsion is designed specifically for installing a wide range of rubber sheet and tile floorcoverings over sound, smooth and dry subfloors of concrete and sand/cement screed, plywood and flooring grade chipboard and hardboard. It provides high bond strength, to prevent rubber floorcoverings moving when subject to heavy traffic, and the strong initial grab required to stop movement of floorcoverings during the installation.

Q. We’re looking to install aluminium stair nosings onto a steel box section in a high-traffic, public area. Will Stycco Flex be suitable?

A. Absolutely! Stycco Flex, F. Ball’s highly-versatile, flexible tube adhesive can be used to bond almost any materials found in the flooring and construction industries. The high strength build-up and rapid curing time of Stycco Flex means it can secure stair nosings and trims in as little as 60 minutes, without the need for mechanical fixings. The surfaces must be completely clean and a mist of water should be applied before the application of the adhesive.

Q. A customer is requiring a wearing surface in an indoor area that will be used for valeting cars. Will Stopgap 850 Exterior be suitable?

A. Yes, it will. It can be left as a stand alone wearing surface and is hard wearing enough that cars can be driven on it. It’s ideally suited for outdoor use because it is unaffected by rain or frost once set. It can also be used in indoor areas that may be subject to surface water due to its moisture tolerant formulation.

Q. I’m installing floorcoverings over a newly-installed concrete screed. Will a waterproof surface membrane be required?

A. Almost certainly. A recently-installed concrete screed is likely to contain a large amount of residual construction moisture, which can potentially cause complete floor failure if no waterproof surface membrane is in place to stop it rising up to the level of floorcoverings. You will need to leave at least seven days between the screed being installed, grind off any laitance and make sure it is completely clean, smooth and dust free. Then conduct a moisture test to determine subfloor relative humidity (RH) levels. A waterproof surface membrane will be required where subfloor RH levels are above 75% (65% where wood floors will be installed).

Q. Can I apply Styccobond F44 straight over a screed with underfloor heating?

Styccobond F44 can be used for securing vinyl sheet and tile floorcoverings to a wide range of subfloor types, including concrete, sand/cement screed and plywood, as well as Stopgap levelling compounds. The screed must be structurally sound, smooth and dry, and any underfloor heating systems must be turned off 48 hours before, during and after application. You may consider applying a levelling compound beforehand to create a perfectly smooth base for the receipt of floorcoverings to avoid imperfections in the finished installation.

Our technical team are on standby to answer questions about your projects and F. Ball products from 7.30am – 5.00pm, Monday to Friday.

Please note: site conditions vary. Don’t rely on these specific responses for your own project. If you are unsure about any technical issue relating to specific flooring installations, contact the F. Ball Technical Service team on 01538 361633 or consult the product data sheets available from F. Ball’s website.