Refurbishment and maintenance make up about 40% of all construction output in the UK, and as we emerge from the Covid-19 crisis, the need to ensure buildings across the country are still fit-for-purpose following months of lockdown could mean this figure rises.
Now is therefore the ideal time to remind yourself of some of the key considerations when it comes to refurbs. Here are five rules-of-thumb that it’s worth any flooring contractor keeping in mind when embarking on a refurbishment project.
1. Consider the age of the building
The first thing you should do is ascertain when the building was completed, as this provides an important clue as to the type of materials that were likely used.
For example, if the building dates back to before the ‘70s, the likelihood is there’ll be no base damp-proof membrane (DPM) in the floor. If the building was completed in the ‘70s or since, then the chances are – assuming it was designed to be habitable – that a base DPM will be present.
2. Which floor is the refurb taking place on?
The next thing to consider is whether the refurb is taking place on an upper floor or a floor that’s in contact with the ground. If the work is above ground-level, the subfloor will probably be dry (the exception is cases where plumbing, showers, toilet blocks, etc have caused leaks). If the floor is direct-to-earth, it may well have been subject to moisture migration.
3. Remember moisture readings can be unreliable
Moisture tests on refurbishment projects can be somewhat sketchy, with the results saying more about recent weather conditions than the continuing condition of the subfloor. Test during a summer heatwave and the results are likely to say dry; test in winter, when the land is heavy in moisture and the heating is turned on, and the results are apt to show significant moisture migration. If you get a wet reading you need a surface DPM. If you get a dry reading you may still need a surface DPM unless it can be determined that there is a base DPM in the building.
4. Assess which materials can be left in place and which must be removed
While all floor coverings should ideally be removed to return you to a strong, sound base, the practical realities of many jobs today mean this isn’t always possible. Consequently, a key part of many refurb projects is identifying which present materials may be left in place and which must be removed.
For example, a solid terrazzo floor is in itself a good surface, and can be cleaned up and DPM’d on a ground floor or suitably primed on an upper floor before applying the smoothing compound. The same applies to quarry tiles and ceramics.
On the other hand, moisture-sensitive floor coverings such as Granwood and magnesite must be uplifted from direct-to-earth areas, while resilient sheets, tile flooring and cork should be removed wherever they are found.
5. Don’t skimp on smoothing compound
It’s the smoothing compound that will act as the absorption medium and provide strength for the entire floor, so ensure you don’t skimp on it but always apply the recommended amount. Equally important is selecting the right smoothing compound for the specific needs of the application.
For example, Bostik SCREEDMASTER SL C951 DEEP can be applied between 5mm and 50mm, making it suitable for smoothing uneven subfloors and raising floor levels, while our SCREEDMASTER SL C910 SPEED 30 smoothing compound is the perfect solution for time-sensitive refurbishments, as it has a walk-on time of just 30 minutes and allows you to bond the floor coverings from three hours.
This has been a brief overview of some of the main things to consider, but there are several other factors that come into play, not least the floor type you’re installing. It’s also important to remember every refurbishment is different and that, as a result, no ‘one-size fits all’ approach exists. Above all, proceed carefully, apply common sense and experience, and when in doubt, contact the manufacturer’s technical team for advice.
Written by Martin Cummins
