Focus on floors: your questions answered

F.Ball Stopgap 800 Floor Application, Presecot Street, London, 5th August 2016.
In this focus on floors, we pick some frequently-asked questions and the responses we provided from the past few weeks.

Q. I’m installing carpet over a calcium sulphate screed, what should I do?

A. Calcium sulphate screeds need to be properly prepared ahead of the installation of floorcoverings. Firstly, ensure the subfloor is completely dry (less than 75% relative humidity) and free of laitance and dust. It’s essential to prime ahead of the application of the levelling compound. Stopgap P121 is F. Ball’s specialist primer for calcium sulphate screeds. It is applied in two coats; the first diluted with one part water for every one part primer; the second neat. You should ideally choose a compatible, calcium sulphate-based, levelling compound, such as F. Ball’s Stopgap 1100 Gypsum.

Q. When applying Stopgap 1200 Pro over Stopgap F77, is it essential to prime beforehand?

A. As long as it’s within 24 hours of the waterproof surface membrane being applied, it’s not essential to prime before applying Stopgap 1200 Pro. However, where underfloor heating is present, or if it is more than 24 hours since a waterproof surface membrane was installed, prime with neat Stopgap P131 or Stopgap P141.

Q. Can Styccobond F49 Hybrid PS be used over underfloor heating?

A. Yes, Styccobond F49 is perfectly suitable for use over normal underfloor heating systems. You just need to switch off the heating at least 48 hours prior to the installation. The underfloor heating should remain switched off during the installation and for 48 hours afterwards too.

Q. A customer has requested a solvent-free adhesive for installing wooden blocks. What can I use?

A. F. Ball’s Styccobond B95 is a high-performance, one-part, flexible, moisture curing polyurethane adhesive for installing a wide range of wood floorcoverings. It’s quick to set and develops a high bond strength. It is both solvent and isocyanate free.

Q. What adhesive should I use to install luxury vinyl tiles in a conservatory?

A. Floorcoverings in conservatories are likely to be exposed to extreme temperatures and changes in temperature. As a result, vinyl floorcoverings will expand and contract, causing unsightly tenting and gapping over time. Styccobond F49 Hybrid PS builds up an ultra-high bond strength to hold floorcoverings firmly in place over a wide range of temperatures, as low as -20°C and up to +60°C, ensuring optimum dimensional stability. It’s pressure sensitive qualities make it easy to work with and ideal for the installation of LVTs.

Q. I’m looking for a heavy duty levelling compound for a warehouse.

A. Both Stopgap 300 HD and Stopgap 800 Wearcoat are suitable for use in light to heavy duty applications, in areas that will subject to heavy loads or high footfall, such as corridors, storerooms and warehouses. It depends if you need the surface to be a stand-alone wearing surface or you will be installing floorcoverings. Where floorcoverings are not required, Stopgap 800 can be used as a standalone wearing surface. If you’re applying Stopgap 800 in areas where water or other fluids may occasionally spill and come into direct contact with the cured material, the surface should be sealed with Stopgap Seal.

Q. What’s the best way to conduct a moisture test?

A. A Protimeter will be able to give an indication of the levels of moisture present in a subfloor almost instantly. However, where a Protimeter indicates that there is subfloor moisture present, it’s advisable to then use a hygrometer to determine the precise moisture levels, in accordance with British Standards. Where a digital hygrometer indicates relative humidity levels in the subfloor are above 75% (65% if wood floorcoverings are to be installed) a waterproof surface membrane may be required to prevent possible floor failure.

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

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.