Now is the time to turn up the heat – literally – to create the right conditions for
flooring installations. Rob Russell explains…

THE long, hot summer days are behind us, temperatures have dropped sharply, and while it’s tempting to dwell on the gloom, we need to shine a light on the challenges ahead and take proactive steps to ensure successful results.

In winter, flooring contractors frequently encounter inadequate heating on-site, with ambient temperatures often falling below the recommended 18deg C required for installation.

Buildings also tend to exhibit temperature differences between the ambient air and the subfloor, with the subfloor usually being cooler. Crucially, the subfloor surface temperature must never fall below 10deg C to ensure optimal adhesive performance and flooring installation.

Best practices, manufacturer guidelines, and British Standards all set out clear requirements for site conditions, acclimatisation, and adhesive use. But in reality, projects rarely meet these ideal conditions. So, what challenges do flooring contractors face when the environment isn’t right?

One of the biggest challenges is achieving site conditions that replicate those of a completed, occupied building. Without this, adhesives, smoothing compounds, DPMs, and floor coverings may not perform as intended. The priority must always be to create the best possible environment – often requiring the introduction of heat. Unlike many trades, flooring installation is highly sensitive to temperature and cannot be carried out effectively in cold conditions.

What the British Standards say
BS 5325, BS 8203, BS 8204 and BS 8425 advise that for most flooring installations, a consistent work area temperature of between 18-27°C should be maintained throughout the installation period.

Temperature and humidity should closely match the conditions in which the flooring will actually be used. British Standards also advise that this temperature should be achieved at least 48 hours prior to installation to allow flooring materials to acclimatise. Just as importantly, temperatures must be maintained for 24 hours after installation, or until the adhesive has cured.

Heating options
Using propane burners may seem like a quick fix, but they can raise moisture levels in the building, which negatively affects drying and curing times. In contrast, warm air blowers are more effective, especially when heat is circulated evenly throughout the space rather than directed at a single area.

Commissioning an underfloor heating system is another solution, helping to bring the building up to the required temperature. However, this and other measures often incur costs that are overlooked – or avoided. If this leaves you in a cold situation, your first port of call must be a conversation with the main contractor or client. They must understand that poor site conditions increase the risk of installation failure, extend completion times, raise costs, and compromise overall quality.

The pitfalls of cold conditions
Smoothing compounds: Drying times are based on 20deg C. Colder temperatures mean extended drying, delayed installation, and longer traffic-free periods to avoid damage.

Fast-curing products: These are available but add cost. Wouldn’t it be more cost-effective to heat the site properly in the first place?

Water-based products: Cold conditions increase viscosity, making them harder to spread and reducing flow. In practice, you may need more product to achieve the same coverage.

Adhesives: Waiting times in the cold are significantly longer, with optimum open times extending up to three times longer compared to 20deg C. Again, time is money – heating is the long-term answer.

Floorcoverings: Materials such as vinyl retain their ‘memory’ in colder conditions, and when combined with adhesives that cannot cure or bond properly at low temperatures, they become much harder to lay flat. This isn’t a product fault but a direct result of inadequate site temperatures.

Timber flooring: Moisture content is critical. Cold conditions can increase wood moisture, causing expansion. Once the environment warms up, gapping occurs – ruining the floor’s appearance. Solid flooring is particularly unforgiving, with gaps becoming even more apparent once stained or sealed.

Communication is key
Conversations with clients about low site temperatures are critical. Relying on optimistic disclaimers is not enough. Everyone involved needs to understand that poor conditions lead to failures, delays, higher costs, and compromised quality. Open dialogue is the first step to securing the right environment for success.

The CFA’s Winter Warning campaign is an excellent resource, and its guidance should be written into contracts with main contractors.

Heating may feel like an additional cost, but compared to the price of replacing failed flooring, it’s a bargain.

rob.russell@bostik.com
www.bostik-profloor.co.uk
Rob Russell is technical consultant, Bostik UK