Damp Proofing Specialists In Sheffield And Chesterfield.
Damp Proofing From Groundwater And The Effects Of Rising Damp.
The issue of rising damp has been known and documented since ancient Greek/Roman times.
There was a Public Health Act introduced in Victorian times in which it was made compulsory for housing to require a damp proof course in the walls to prevent rising damp.
Although some materials appear to be dry, most sill contain some type of moisture.
Moisture can be present in the structure of a building through either condensation from within the building structure, rain water, or from 'rising damp'.
Rising damp is a common term used for the slow upward movement of ground water in a buildings walls through the process of capillary action.
The damp rarely rises above 1.5m but has been seen to rise up to 5m in extreme circumstances. The ground water comes into contact with the sructures' walls and moves upwards through porous building materials such as brick, sandstone and mortar.
You've probably seen this kind of action in something like the oil that moves up a wick on a candle or oil lamp. If you place a piece of paper into oil or water whilst still holding it in a vertical position, you will see the fluid travel up the paper.
Using porous materials such as brick and water obviously never work well together as far as preventing damp in the building is concerned. Aswell as many different types of water resistant creams injected into the brickwork, builders also turn to what is known as Staffordshire Blue Bricks.
Staffordshire Blue Bricks get their name from the distinctive blue colour they turn after being fired in the kiln. The original colour is red made from the local clay. After being fired it not only turns blue, but also becomes very hard with a high crushing strength and low water absorption ( around 4.5% ).
With rising damp, you will usually see a water 'tide mark' which is caused by the soluble salts found in ground water ( nitrates and chlorides ).
insert image of ground water levels in Sheffield.
With adding a damp proof course a layer can be added via DPC ( damp proof course ) injection. Usually a liquid or cream is injected to line the pores of the mortar and brick work.
Alternatively some form of waterproof membrane can be laid. See the Delta Terrax Membrane.
Additional damp proofing measures include land drainage and re-plastering. Land drainage can be used to try to minimise the contact between the ground water and the structure of the building.
Having the walls re-plastered can be effective when used in conjunction with any of a variety of water resistant and salt resistant adhesives.
Damp Proofing The Space Under Your Floorboards.
Damp proofing the space under your floor boards. The crawl space under your floor usually looks like the 1st picture below. Dirty, damp and cold.
Air is circulated through vents in the walls to prevent the timber floor joists from rotting. Cold air is drawn up into the warm building bringing with it the damp from the earth floor below.
To prevent this and possibly even more important, to save money on heating, we can line out your crawl space with clean space lining.
We may also fit a drainage sump in areas that are prone to flooding, and if humidity is a problem, we also install specially designed de- humidifiers in the clean space too.
An Example Of Damp Proofing Work.
Call us today and ask us about damp proofing in Sheffield.