Victorian house in need of love. Damp proofer with a thick membrane.
- Look for the signs of past damp proofing treatment, these typically cause the worse damp issues, as they block the movement of liquid and gaseous water, rather than allow a wall to absorb and evaporate water naturally.
Penetrating damp, damp proofing treatment and excess humidity.
The house has been damp proofed against rising damp by injecting chemicals. Typically, damp proofers replace ground floor internal plaster with an impermeable plaster. In this case a plastic membrane has been installed.
There are many damp issues, possibly more damp issues will become visible after initial remedial actions.
Damp results from four primary sources, a mains leak, rainwater, groundwater (rising damp) and condensation. Penetrating damp and condensation are the two forms affecting this property.
This property has had various forms of damp proofing treatment, which appear to have made problems worse.
Plastics and impermeable paints affect the way walls absorb and evaporate water.
By the front door there is timber affected by rot and woodworm.
The rot is a brown, wet rot called Coniophora puteana, or cellar rot, a brown wet fungus that causes cuboidal cracking. As is often found alongside Coniophora puteana, there is an infestation of wood weevil, increasing the rate and scale of damage. Rot requires water to grow. Wood weevil requires rot. Remove the water and both will stop destroying timber.
The lower wall was dry, which it would not be if there was rising damp.
Readings below 20WME are considered dry. The range is 8WME to 99WME. See https://surveyor.tips/dampmeter. Walls measured were largely dry on the surface except where mentioned in this report. Readings below 20WME are considered dry. The range is 8WME to 99WME. See https://surveyor.tips/dampmeter. Walls measured were largely dry on the surface except where mentioned in this report.
Water has become trapped behind the impermeable surface.
It would be better to remove the impermeable coating.
The neighbours drain their rainwater down-pipe away from the building. It had become dislodged.
I refitted the neighbour’s down-pipe. This should be regularly checked and ideally screwed in place.
There has been a plastic membrane fitted to the front bay wall.
This type of treatment normally causes problems with absorption imbalance. It would be better removed. Consider installing thermal insulating plasterboard floor to ceiling, to create a homogenous surface.
There are some crack to external detailing, such as this window sill and around the windows.
Cracks should be filled, smaller cracks with an external acrylic caulk.
There is tanalised timber to the front, suggesting a severe case of rot in the past.
Consider wedging the timber in the sub-floor to reduce the risk of damage.
There was damp to the rear kitchen wall, again dampness has become trapped by an impermeable barrier.
Kitchens are at risk of condensation. Install a kitchen extractor fan and use it when cook.
There is no externally ducted kitchen ventilation.
Ventilation is most effective when air is extracted close to the vapour source; bathroom, kitchen, drying clothes and occupied rooms. The internal ventilation does not meet Building Regulation 2010 Part F requirements. This is best achieved with mechanical extractor fans.
See P39 and P19 in https://surveyor.tips/vent_regs specifically:
- Bathroom 15 l/s with a 30-minute overrun.
- Kitchen 30 l/s adjacent to hob; or 60 l/s elsewhere in kitchen.
Neither bathroom has sufficient ventilation, resulting in condensation in the loft extension.
This electrical sock has rust in the centre, this is a sign of excess humidity causing rust.
Sockets require a section to be cut out and replaced with a metal box, this causes localised heat loss increasing the risk of condensation, especially on external walls.
The rear reception external wall is damp.
I understand there had been a drain issue, now repaired, in a neighbouring property causing water to back up.
This pipe looks obsolete and if so, should be removed and the hole filled.
The fence post has rotted. This may have resulted from past damp issues.
I tested the drain it appeared to be working well.
It is possible that there are cracks, possibly underground, if so bi-pass the drain with an elbow and horizontal pipe, similar to the neighbours’ from drains.
The wall has vertical damp proofing this suggest the drain was an issue in the past.
Looking under the house the remaining timber appears to be in reasonable order.
There is mould growing in and around the bathroom.
Mould grows where relative humidity exceeds 85%RH for 6+ hours. Excessive humidity results from insufficient ventilation, poor air circulation and a cold surface. See https://surveyor.tips/mould. The secondary cause of high relative humidity is low temperature relative to the source of humidity, see https://survey.tips/humidity.
The brown stains in the front bedroom is a sign of penetrating damp, that is rainwater.
Here the ceiling is dry.
The section of ceiling by the corner of the bay is damp.
Looking from above, we can see plant growth in the corner suggesting that water back-up splashed or leaks out.
The wall looks slight white, that is efflorescence from splashing rainwater. I also suspect that the timber is not providing sufficient protection. You should look to see what is happening during a rainstorm. It may be necessary to extend the bitumen felt roof.
A section of cement filleting has a gap by the right-hand party wall.
You should fill the gap or replace the cement fillet with lead flashing.
The front bedroom is damp above the front door.
There are various gaps around the window sill and window that should be filled.
Despite its look, timber in the loft was dry.
There was a high damp meter reading on the front left-hand chimney breast.
It is possible that there is defective flashing. This was not resulting in internal damp in habitable spaces, so need not necessarily cause a concern.
Looking at the chimney from the rear, there is plant growth suggesting that the flaunching needs repair.
Consider repairing the flaunching and while you are there, installing cowls on the chimney pots.
There rear bedroom wall has past damp issues.
My suspicions are that these are mainly condensation related as there was no brown stain, but is difficult to tell from decoration. I understand that the rear guttering was blocked. I check and found that it was clear during the survey.