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’m installing floorcoverings over marble tiles. What primer should I use?

A. You’ll need to apply a suitable levelling compound to create a smooth base for the floorcoverings, so you’ll need to apply a primer over the tiles to promote adhesion. F. Ball’s newly launched Stopgap P141 primer will work perfectly for this. It creates a textured finish to provide enhanced bond performance between non-absorbent subfloors, like marble tiles, and to receive Stopgap levelling compounds.

Q. Can Styccobond F3 be used to secure vinyl floorcoverings in a wet room?

A. Styccobond F3 is predominantly used for securing textile floorcoverings. The traditional solution for installing resilient floorcoverings in damp and humid environments is to use an epoxy or polyurethane adhesive, which are effective at making areas impermeable to water. Nowadays, there’s another option: Styccobond F49 Hybrid PS, a water-based vinyl adhesive developed to provide the ultra-high bond strength required to hold floorcoverings in place where they are subject to extreme temperatures and temperature fluctuations. These properties also make it resistant to wetting.

Q. I need to repair damaged concrete stairs and then fit nosings.

A. Begin by cutting back the concrete to the sound level of the subfloor and apply Stopgap 400 repair compound to any cracks or holes. Then use Stycco Flex, F. Ball’s rapid-curing, flexible tube adhesive, to secure the stair nosings. The high strength build-up and fast curing time offered by Stycco Flex means it can secure stair nosings and trims, without the need for mechanical fixings, in as little as 60 minutes.

Q. Can I use Stopgap F78 over a gypsum screed?

A. We don’t recommend this. If, when you conduct a moisture test, you find that the relative humidity levels in the subfloor are higher 75% (65% if wood floorcoverings are to be installed), you should allow the screed to completely dry. Unlike concrete, calcium sulphate screeds dry from the bottom up, so a moisture test may deliver a positive reading right up until the point the subfloor is completely dry. So be patient. You can speed up the drying process by opening windows or using a dehumidifier. You can then proceed to preparing the subfloor without the need to apply a waterproof surface membrane.

Q. I need a levelling compound for use over plywood.

A. You’ll need a flexible levelling compound. Stopgap 700 Superflex is designed specifically for use over plywood and can also be used over raised steel subfloors, concrete and sand/cement screeds too. Stopgap 700 Superflex is reinforced with tiny fibres that allow it to cope with the inherent movement in flexible subfloors, such as plywood, meaning that any movement caused by foot traffic or point loading will not compromise the integrity of the underlayment.

Q. Can I apply Stopgap F77 over Stopgap 1200 Pro?

A. Yes. When a waterproof surface membrane is required to suppress excess subfloor moisture levels, it’s sometimes best to apply a waterproof surface membrane over the levelling compound first, rather than the other way around, as usual. For example, where rough or uneven subfloors would cause the waterproof surface membrane to pool, compromising its effectiveness and reducing coverage rates, thereby increasing costs. When applying a waterproof surface membrane over a levelling compound, it’s important to make sure it’s a moisture tolerant levelling compound, such as Stopgap 1200 Pro, Stopgap Green Bag/114 or Stopgap 850 Exterior.

Q. What adhesive should I use for installing artificial grass indoors?

A. If the area isn’t required to be resistant to water, you can use Styccobond F3 to secure some synthetic grass carpets indoors. However, you should always refer to the floorcovering manufacturers installation instructions or consult the F. Ball Recommended Adhesives Guide.

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.