Damp in homes is a common building defect found during building inspection and it can happen from many different sources. Damp may cause many other problems in the property such as termite infestation, mold, rot, rusting, and strain on the walls. It can also lead to health hazards.

A building inspection can reveal the presence of damp and source of damp in the property. A good building inspector uses a moisture meter to determine the level and source of damp in homes. There are mainly 3 types of damp – rising damp, penetration damp, and condensation damp. Building Inspection Council has compiled the information about damp to help Australian property buyers.

1. Rising Damp

What is rising damp?

Rising Damp - Building Inspection CouncilRising damp is groundwater moving up through the wall. Wall materials are porous and allow little water in. This water can move up through the wall by capillary action if not stopped by a barrier called damp proof course. If this membrane does not exists or is damaged then water can keep rising causing damage to walls.

What are signs of rising damp?

As rising damp in home is caused by water moving up through the wall so damage is caused at the base level of the wall. The common signs are

  • Damaged skirting, floorboards,
  • Strains or marks in form of tide
  • Peeling paint or wallpaper
  • Musty Smell.

What are treatments of rising damp?

To deal with the rising damp, you need to find the cause of it. It is advisable to call an expert to carry out a detailed assessment of the damp-proof course.

  • If the damp-proof course fails then you need to inject damp-proof liquid or cream.
  • Managing the water drainage slopes
  • Managing the soil level in the garden below the damp-proof course.

2. Penetration Damp

What is penetration damp?

Penetration Damp - Building Inspection CouncilAs the name suggests, penetration damp in homes happens due to penetration of water from outside or water leaks in the walls. Water moves in the horizontal direction and may expand across walls or ceilings in any part of your house. The penetration damp happens due to the structural issue in the building such as cracks in the walls, damaged or clogged gutters, leaking roof allowing water in.  Another reason is internal leaks from broken or rusted water pipes. Older houses with solid walls are more prone to penetration damp.

What are signs of penetration damp?

  • Damp Patches or strain on the walls and ceiling
  • Wet plaster which is cold to touch
  • Large bubbles in the plaster

What are treatments of penetration damp?

To fix the penetration damp, you need to identify the source of water or leak first and then arrange a proper repair of the issue. You can also consider

  • Applying and maintaining water paint on the exterior of the house
  • Regularly checking for any water leak or water penetration
  • Maintaining ventilation around the damp-proof course.

3. Condensation Damp

What is condensation damp?

Condensation Damp - Building Inspection CouncilCondensation damp in homes is wetness due to condensation of the warm humid air inside the building. The condensation happens when warm humid air comes in contact with relatively colder walls. The amount of humidity in the air directly affects the condensation damp. The most common areas for condensation damp are the kitchen and washrooms due to high moisture in the air. Central heating and poor ventilation make the problem worse as it allows the warm air to condense.

What are signs of condensation damp?

The main signs of condensation damp are

  • Water droplets on windows and walls
  • Mould building around window and on walls
  • Unpleasant musty odor
  • Damage in paint or wallpaper

What are the treatments of condensation damp?

As lack of ventilation is the main cause of condensation damp so improving the ventilation in the building will fix most of the problem.

  • Remove any obstruction to the ventilation of the air in the building
  • Avoid drying clothes inside
  • Install exhaust fans at key points to improve ventilation

Dampness is a serious problem and only an experienced building inspector can identify the dampness and its source. There could be major structural defects underneath the dampness. So fixing the damp and source of it could cost a huge amount of money. It is important to have an independent building inspection done before signing the dotted lines.

Building Inspection Council is a not-for-profit community service that helps Australian property buyers with free building inspection quotes. We verify each building inspector before they are allowed to send you quotes so get quotes from genuine expert building inspectors who can reveal damp in homes. As a not-for-profit organization, we do not have to compromise on anything for profit and you get expert quotes from your local inspectors. FOR FREE QUOTES. CLICK HERE.

Building Inspections reveal 3  types of damp found during inspection – rising damp, penetration damp, and condensation damp. Rising damp happens due to the upward movement of groundwater through walls. Penetration dampness happens cause of water penetration from outside and condensation damp happens due to condensation moisture in the air.

Following are the signs of damp found during the building inspection

  1. Stain marks on the walls
  2. Musty unpleasant odor
  3. Building of mold in the property
  4. Peeling of paint and wallpaper
  5. Damaged skirting and underfloor
  6. Forming of the bubble in plaster
  7. Droplets on windows and walls

For more information you can read ” DAMP HOME – TYPES, SIGNS, AND SOLUTIONS“.

You can prevent or fix damp in the building using the following solutions.

  1. Ensure the soundness of the damp-proof course
  2. Always keep surface level below the damp-proof course
  3. Maintain proper ventilation in the building
  4. Monitor and repair internal water leaks
  5. Apply waterproof coating on external walls
  6. Install exhaust fans at key points to help ventilation
  7. Seek professional help

For more information, you can read ” DAMP HOME – TYPES, SIGNS, AND SOLUTIONS“.