Protection against water ingress and moisture

A garden shed is exposed to the elements 365 days a year – heavy rain, meltwater and rising damp. To ensure your garden shed remains in pristine condition for generations to come, DESIGA employs a three-stage protection concept comprising waterproofing, active drainage and structural ventilation. This follows our guiding principle: prevention rather than cure.

Stage 1 – The internal seal as the centrepiece

A continuous profile seal between the foundation and the sill reliably keeps rainwater out. It is designed to compensate for tolerances in the foundation of up to 4 mm – both against splash water on the weather-facing side and against moisture that could rise through capillary action.

Stage 2 – Active drainage in critical areas

In the area of the floor-to-ceiling sliding door and along the main weather-facing side, we recommend installing a gutter in the foundation. This actively channels rainwater away from the building. Even during heavy rain with high driving rain loads, this prevents water from pressing against the threshold. A slight slope away from the house further reduces the risk.

Stage 3 – Protection through spacing and ventilation

The adjustable feet of the timber sub-frame, made from C24 solid structural timber, raise the entire subfloor 30 to 50 mm off the foundation. This air gap interrupts the capillary effect – ground moisture cannot rise into the timber. The continuous rear ventilation keeps the material dry and ensures a permanently healthy indoor climate.

Important note: If the floor unevenness exceeds 4 mm, the profile seal alone is not sufficient. In this case, the foundation must be reworked or additional drainage installed along the walls on site.

What does this mean for you?

You are investing in a garden shed designed to last for over 50 years – without moisture damage, without mould, without renovation costs. Protection starts at the foundations, long before the weatherproof HPL cladding comes into play.