how to treat damp in a terraced house and how to renovate a terraced househow to treat damp in a terraced house and how to renovate a terraced househow to treat damp in a terraced house and how to renovate a terraced house



One of the most prevalent problems in older properties that you will encounter during a property renovation is Damp.

Damp can rear its head in many ways, rising damp, penetrating damp, and damp caused by condensation.

In this property we encountered them all!, and we treated them as follows:

Damp was found in the ground floor, properties of this age didn’t have the luxury of a visqueen membrane beneath the floor, quite often quarry tiles were laid over a thin cement based screed, which was then laid over ash, or sometimes just soil ( some properties have a timber ground floor which can be susceptible to dry and wet rot too ) in this case, the floors were mainly dry, with the odd isolated patch of moisture and didn’t warrant the floors being removed and re-concreted. However they were out of level somewhat due to settlement over the years. Our treatment was to apply a levelling treatment of mastic asphalt to the low areas, followed by a top levelling coat to improve the levels of the floor. the mastic asphalt is laid in a couple of hours, and can be walked on a couple of hours thereafter, thus saving time on the job and more importantly providing and impermeable membrane to prevent moisture rising through.

Rising damp was not really an issue in this property, however as we had removed all of the plaster it made perfect sense to install a horizontal DPC by means of drilling and injecting the brick / mortar courses with DRYZONE cream a link to their data sheet can be found this data sheet provided by the manufacture also gives instructions on how to install the product. Having used dry zone for years we find it the easiest of products to use, its a low odour product and providing the instructions are followed we have found it to work well.

Penetrating Damp – Often confused as rising damp or condensation, is quite prevalent of the first floors, mainly due to the roof being old and unfelted. The problem with damp, is that after plaster ( introducing more moisture into the property ) the dampness can remain in the bricks and rear its head later as staining or marks on the plaster. To avoid this we applied a tanking mortar to the chimney breasts where flashings have failed on the chimney causing water to run down, and we also applied tanking mortar to the entire property unto 1.00m from the floor to prevent any future problems coming back into the house. Tanking mortar, often used in cellars, swimming pools etc provides a impervious surface which holds back water and damp ingress.

We are about to fit PVCu windows to the property, a lot of homes had windows replaced with PVC, but unfortunatley what this appeared to do was to make the home a lot more “sealed”, and didn’t allow any background ventilation into the home. This coupled with the fact that the properties were thermally inefficient in many other areas led to a build up of condensation within the home – this may appear as mildew, beading of water around the windows, and general dampness in the home. To prevent condensation damp from appearing in the future all of our windows are fitted with trickle ventilation, This allows a background ventilation to the rooms and permits air changes in the home therefore assisting with the avoidance of condensation.

Look out soon for the window installation, the roof replacement and first fixes electrically, plumbing and joinery!

if you are thinking of carrying out a home renovation in stoke on trent, staffordshire, cheshire or shropshire, feel free to call us for advice or a free quotation on your home renovation.