Liquid waterproofing & flat roof coating

Sheet materials are only as good as the shape of the roof they are laid on. Give them a cluster of pipe penetrations, a rooflight, an internal corner and a change of level within a couple of metres, and the number of seams multiplies — and every seam is a future leak. Liquid waterproofing removes the seams entirely.

How a liquid system is installed

The roof is cleaned, prepared and any defective areas of the existing covering are cut back and made good. A primer is applied to promote adhesion, followed by reinforcing fabric dressed into the membrane at junctions, upstands and corners — the places where movement occurs and where most leaks begin.

The ARBOFLEX PU is then applied in coats by roller and brush. Because the material cures as one continuous skin, there are no laps to lift and no fixings to work loose. It remains flexible at low temperature, which matters in an East Midlands winter, and resists standing water without breaking down.

On most roofs we can go straight over a sound existing covering, so there is no strip-out, no skip, and often no need for full scaffolding — which is a significant part of why the total cost frequently lands close to felt replacement.

Where liquid waterproofing is the right answer

It is not the cheapest way to cover a simple rectangular garage roof, and we will tell you so. But on the following, it is very often the best value option on the table:

• Roofs with lots of detail — pipework, plant, rooflights, steps in level and awkward angles, where a sheet system generates seams a metre apart.
• Overlaying an existing sound covering — no strip-out, no waste to landfill, and far less mess for an occupied building.
• Roofs with restricted access — lighter materials and smaller plant requirements than built-up felt.
• Commercial and public buildings where the roof needs to keep working, and where a phased or part-area application suits the building's operation.
• Listed or heritage-adjacent properties where a low-profile, colour-matched finish is preferred to a visibly new roof covering.

We will normally price both felt and liquid where either could work, so you can see the difference in cost and lifespan side by side before deciding.

The ARBOFLEX PU system

ARBOFLEX PU is a single-component, cold-applied polyurethane waterproofing system, supplied through EDS Roofing Supplies and covered by a manufacturer guarantee on qualifying installations. Because it is cold-applied there is no flame on site — often a requirement on schools, healthcare buildings and occupied commercial premises.

Full specification sheets, safety data and product guarantees are provided with every quotation and can be issued to your principal designer or facilities team.