Digging Deep to Get a Seamless Finish

Tremco / 08 August 2022

“When planning flooring projects, the substrate must be one of the first considerations. It is vital to the success of any project because, if the substrate is not properly prepared, the installation will probably fail.

Tremco CPG contractors often turn to our technical experts for advice on how to approach the issue, recognising that this early-stage involvement is crucial to the flooring system’s performance overall. 

Manufacturing companies’ technical representatives can play an invaluable role with the contractor by working together in an initial inspection.

Structural solutions

Out on site, this early inspection can determine the extent and nature of any cracking. 

In certain cases, it can also unearth more serious technical structural problems. 

As part of the visit, this approach is necessary to decide if issues with cracking and damage can be effectively routed out and treated. 

During the visit, the strength of the surface also needs to be established. This may involve the use of an Elcometer 106, which measures the strength of a substrate and will help identify variations in its soundness.

Pitfalls to avoid

The inspection should also pay careful attention to areas like upstands, as well as details such as gullies, drainage outlets and pipe penetrations. All of these are potential problem areas and need to be carefully considered in the process too.

Where a contractor is working on a ‘previously owned' property, an inspection can also help to pinpoint what the building was used for previously, and what likely contaminates from past use are embedded into the substrate. This is important work to undertake, as the past uses a building was subjected to can emerge to cause issues in the flooring installation projects. For example, oils, chemicals and other products used over the years could provide a hidden problem, which can be identified in an inspection of the substrate.

Where an issue is identified, the contractor has several recourses including the use of mechanical means to remove solid material such as mortar spots or old adhesive. 

Where liquid contamination is an issue, this can either be removed using solvents or, for tougher stains, emulsifiers can be applied to 'draw out the pollutant.

Damp matters

One factor which can cause significant issues is damp. This remains a real danger, which will seriously threaten the success of any flooring installation.

The key to managing the scale of the problem is to take hygrometer readings at intervals across the work area, to identify moisture levels.

Bear in mind that there is a strong possibility that properties dating from before the 1970s may have been built without a proper damp proof membrane (DPM) or one that has since failed. 

Where serious doubt about the existence of an adequate DPM persists, or where hygrometer readings - expressed in terms of relative humidity - are above 75% RH, then the installation of a well-proven, fluid applied system is definitely indicated.

Levelling Up

Another important consideration is an uneven substrate surface. In some circumstances, where the substrate is roughly surfaced, it may be necessary to utilise a moisture tolerant smoothing compound prior to installing the DPM. To achieve a uniform finish, a further coat of the compound can be laid to ensure the adhesive and floor covering deliver the desired even finish.

Finally, when conducting all stages of the inspection, specification and installation, it is essential for the flooring specialist to remain mindful of the building's eventual function, to ensure it is fit for purpose in the future.

Occupancy also needs to be considered in relation to the products and methodology chosen. It may, for instance, be appropriate to choose products offering very low odour or that are EC1 compliant to respect locations like hospitals or food production facilities. 

In summary, some detective work is often required to ensure a flooring installation gets off to the best possible start. In all situations, correct preparation remains essential to success and, in this important area, manufacturers are on hand to help contractors achieve the right outcome.”