All You Need to Know About Penetrating Damp

There are different ways that damp can access a property: Rising Damp, Penetrating Dampness, or Condensation. Here we will explore the problem of penetrating damp, and how you can identify and treat it in your home.

What is Penetrating Damp?

Penetrating dampness occurs generally as a result of poor external maintenance, i.e. defective rain water goods (gutters), which will allow rain water to penetrate the structure of the building. This can occur when the external renders are cracked, because of spalled brickwork, or even due to roof defects.

Signs of Penetrating Dampness

  • Wallpaper peeling off, plaster falling off walls, ‘blown’ plaster.
  • Internal plaster stained.

Causes of Penetrating Damp

  • Flower beds, lawns, paths, patios and driveways being raised above the
    installed damp proof course against the external wall.
  • Defective Rain water goods such as guttering that allow water to
    penetrate the walls.
  • Faults in the brickwork or masonry such as missing or cracked pointing.
  • Porous bricks or stones.
  • Roof defects such as faulty flashing, cracked or missing slates or tiles.
  • Missing or defective mastic around windows and doors allowing moisture
    to penetrate.


Dean Webster, company director and CSRT surveyor, visits each property to inspect the areas of concern. Clients are provided with a detailed report on all findings, treatments available, and a breakdown of costs should any remedial works be required.

As a specialist damp contractor you can be assured of the problem being correctly diagnosed and a suitable specification of treatments being provided to resolve the damp problems.

Our surveyor ensures that the source of the dampness is established and defects found i.e blocked gutters, leaking pipes, or uncapped chimney pots, are identified in the report, and rectified to ensure the dampness does not re-occur.

It is sometimes necessary to remove internal plaster to inspect structural timbers within the area i.e. timber lintol and floor/ceiling joists. Sometimes no internal works are required as the walls may dry out naturally over time once the source of moisture has been rectified.

If the plasterwork has been affected, and it is appropriate, it is removed and re-instated using our specialist waterproof rendering system. If required we also skim over, for a plaster smooth finish ready for redecoration.

A long term guarantee would be provided for these specialist damp works.

Recommended Sources for Further Reading on Penetrating Damp

Property Care Association

Take a look at the following page for a wealth of information –

Mr Graham R Coleman B.Sc (Hons)., M.I.Biol., C.Biol., A.I.W.Sc., F.Inst.S.S.E.

You’ll find facts about chemical damp proof courses and re-plastering by the industries leading expert who has written many technical publications and articles. Take a look at his website –

Find Your Answer from our Surveyor

Find your question on our Ask the Expert page where our Director Dean Webster has tried to answer all our FAQs!