How to waterproof cellar walls with Basement Mesh

Baseline Mesh Cavity drain membrane


Baseline Mesh is a high density polyethylene cavity drain membrane which allows the isolation of wet walls above and below ground.

The membrane incorporates a tough HDPE mesh lathing welded to the front face to allow the direct application of various plaster finishes or adhesive ‘dabs’ and plasterboard.

Large 8mm studs provide excellent drainage and ventilation capacity, making Baseline Mesh the choice of professionals for basement and cellar conversions.

  • Internal wall lining with drainage
  • Low and high temperature stability


Baseline Mesh can provide a dry, warm and habitable living space in cellars, basements and other areas suffering chronic damp conditions.

Baseline Mesh can be finished with proprietary lightweight plasters or with a traditional 2-coat 1:1:6 cement:lime: sand render and a skim finish.

It can be dry-lined with bonding plaster, applied in 8mm thick (min) dabs covering at least 50% the membrane surface.

After the plastered or dry-lined surface has dried, it can be painted or papered without any delay.

  • Accepts direct plaster finish
  • High durability and water resistance


Baseline Mesh is suitable for waterproofing in accordance with BS8102:1990 to provide Type ‘C’ drained protection to structures below ground, giving a Grade 3 or 4 dry environment that is suitable for domestic or commercial use.

In basements it is essential that Baseline Mesh is used in conjunction with a suitable sump and pump facility (unless passive drainage is available).

A complete range of ancillaries ranging from pumped drainage systems to mechanical ventilation units are available to ensure your basement conversions provides years of troublefree pleasure.

Prepare surfaces

Replace salt contaminated/­friable plaster. Isolate sources of dampness/­moisture. Treat moulds/fungi with masonry biocide

Method statement

How to waterproof cellar walls with Basement Mesh

Work from the centre of the membrane outwards. Fixings are to be spaced at 300mm centres horizontally and vertically.

  1. Drill 8mm diameter bores through ‘Baseline Mesh’ cavity drain membrane to a depth of 70mm.
  2. Feed 70mm ‘Plaster Plug’ through ‘Plug Seal’ and offer up to pre-formed bores.
  3. Drive the ‘Plaster Plugs’ into bores using a series of light taps to simul­ta­ne­ously fasten the membrane to the wall and provide a waterproof seal at each anchor point.
  4. Interlock non-meshed edge studs, sealing seams between sheets with ‘Waterproof Butyl Tape’. Seal wall/floor junctions with ‘Butyl Corner Detail’

Product specification

Product: Baseline mesh

Material: High density polyethylene

Roll size: 2m x 20m (40m2 )

Sheet thickness: 600 microns

Density: 0.7 kg/m2

Load bearing capacity: 50 kN/m2

Drainage\­ventilation capacity: 5.3 l/m2

How to waterproof cellar walls with Basement Mesh

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