Flood Damage and Flood Repair - How to Repair the Damage From a Flood to Prevent Dry Rot and Water Damage to Walls and Floors

This project is sponsored by Property Repair Systems

Summary: What to do after flood damage in your home. How to repair the damage from a flood to prevent water damage to plaster, walls and flooring. Stop Dry Rot forming by drying out the flood water with a dehumidifier. Advice on when to replace damp course after a flood, and using Renderproof to repair your DPC.

If you need any help with any type of Flood damage, flood repair, timber repair, maintenance or other damp problems Property Repair Systems will be pleased to give you completely free, no obligation advice on 01626 336180. The information you need may be in the project below, if not, call them.

Steps to Follow for Flood Repairs

After the debris has been removed, including any floor coverings, damaged plaster and plaster board you need to take the following steps;

  • Check your Insurance cover and advise your Insurers - take as many photographs as you can BEFORE disposing of any household contents: you may need evidence to prove your losses.
  • Clean and check the drains, air bricks (if you have a timber floor down stairs) and wash out all debris with fresh water. If sewerage is involved you should sterilise the floors and walls.
  • Ask a gas engineer, plumber and an electrician to check the services before using them.
  • Hire a dehumidifier and shut all doors and windows in the damp areas. Install a Humidity Meter to monitor the dampness in the air in the building. Install a large enough dehumidifier (or several) until you can bring the Relative Humidity below 60% on the meter (click here to look at Meters).
  • If timber floors are affected, lift boards and clean out the void underneath, including the air brick holes. If you are using a dehumidifier leave some boards up and fit temporary covers to the air bricks, to avoid trying to dehumidify the whole of the UK.
  • Mesh membrane

    Mesh Membrane - it provides a dry decorative surface fast for plaster or plasterboard, available from Property Repair Systems

    Air gap membrane

    Kontract Air Gap Membrane - cover damp or salty areas, before lining or plasterboarding

  • Keep a chart recording how much water your dehumidifier is producing - this will enable you to tell when most of the added water has been removed. You should see a sudden drop in water output, after several weeks, or even months. A hygrometer may also come in handy here in order to measure the moisture content within each room of your home
  • When it comes to walls and floors make sure that they are thoutghly sterilised with a suitable sterilising solution. This way you can then ensure that any bacteria or viruses from sewage are wiped out and cannot cause any future contanination or risk to health
  • Check and record the moisture content of your walls and timbers regularly - a simple electrical damp meter will give a good guide to progress. You are looking to bring timbers below 18% and masonry below 2%, but contaminating salts may leave you with higher readings so be wise to this.
  • It is really essential that all wall and floor areas are allowed to dry out completly before you attempt any form or internal redecoration but in some instances this is not possible. In this situation you may need to use a tanking product to seal the damp away from internal wall or floor areas so that they can be repaired and redecorated. Before you do so, it is a wise idea to get these areas checked out by an expert as by tanking an area you are effectively sealing the damp or moisture in and this could cause more issues later down the line. If you do need to use such a product then Property Repair Systems supply a very good tanking slurry
  • Walls should only be replastered using sand and cement render containing a salt inhibitor and waterproofer - the specification is critical if you are to avoid salts from emerging later and ruining your decorations. A product called Renderproof is a great solution and can be mixed in with your sand and cement. It then acts as a salt inhibitor, plasticiser and waterproofer - click here to learn about re-plastering and whats involved
  • When it comes to older walls, they may benefit from the use of a plastic lining membrane (pictured above), rather than sand and cement - these membranes are easy to fix, waterproof and can be plastered or boarded immediately. They improve the warmth of the walls and floors, can carry insulation and prevent any damp or 'salts' from reaching the decorations. in terms of salts mentioned above, it is also a good idea to treat any walls with a salt neutraliser before plastering or lining as it kills off the slats and prevents them from coming back and ruining interior decorations at a later date
  • Timbers and walls may grow mould - keep the humidity below 60% to avoid this. Again, use a damp test meter or humidity meter to monitor moisture levels in materials and also a hygromter to keep track of humidity levels
  • Damp Meter

    Damp test meters available from Property Repair Systems


    Hygrometer humidity meters available from Property Repair Systems

  • Timbers may also be attacked by wood rotting fungi and insects. Check that the timbers have dried below 18% or consider treatment using Boron based pastes or gel(click here to learn about treatments).
  • Dry rot is a possibility - you can install simple test sticks in vulnerable walls and timbers to check if rot is occurring - they change colour from blue to yellow (click here to learn about Dry Rot Test Sticks).
  • Where timbers have been damaged beyond repair these can be relatively easily fixed without the need for replacement of the whole beam or joist. With the beam or joist supported suitably to take any load weight, the damaged section can be cut off and a new section can be spliced on using a timber resin splice kit, find out more here
  • Monitor the condensation levels with your rooms along side using the above mentioned damp testers. To check these levels you can use condensation test strips. Place these on your coldest walls and they will change colour when condensation is present
  • Speak to real people now on 01626 336180 - qualified staff can provide immediate free advice, to avoid unnecessary work and expense - telephone calls are at normal, national call rates.

In terms of future-proofing yourself and your property from floors, a handy products to have around are self filling sand bags. They store flat and dry and when needed just wet the bag and the gel powder inside expands to fill it automatically.

Don't fancy doing this project yourself? We work with Plentific to ensure that we recommend only reliable and trustworthy tradesmen.

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