Causes Of Damp In Buildings
Causes of Damp in Buildings
Maintaining a property might be a necessity, but it can also feel like a constant, niggling pain. Speaking of which, damp is one of the biggest headaches of all.
Unwanted but just about inevitable - damp is, simply put, unwanted moisture. It can lead to rot, plaster can deteriorate and wallpaper can blister and loosen. The growth of mildew and mould is unsightly and can allow bacteria and fungi to flourish – even causing respiratory problems such as Asthma. And if, say, floor timbers are affected, damp might also cause structural problems.
All of this might lead to a vision of some poor, afflicted ‘house from hell’ but damp does not discriminate. Every building is prone, because there is (just about) no escaping the causes.
Invariably there are three of them:
Condensation
This is a 100 per cent certainty – since living in a house implies (we certainly hope) that you are breathing in it as well. That creates moisture, as do everyday actions such as cooking, bathing, washing and drying clothes.
Therefore, the air gets wetter and when it can’t hold any more moisture, water will gather on cold surfaces such as windows, tiles and walls.
The colder the room, the worse the potential problem. Yet simple steps can help prevent it from taking hold:
-
- When cooking always use pan lids and open a window to ventilate the kitchen
- When drying clothes, try and do it outside. If you live in a flat, or it’s pouring down, use a clothes horse in a room that’s cool (but not cold)
- Don’t dry clothes on radiators: this is one of the main causes of condensation and can cause mould growth on wallpaper and soft furnishings
- If you use a tumble dryer, and if it isn’t self-condensing, make sure it is vented
- When bathing, run the cold tap before the hot; this will reduce the amount of steam produced. It’s also much safer, particularly if you have small children
- Open the window a little to reduce moisture in the room
- After bathing or showering, wipe down the tiles to remove the surface water. Then open the window and shut the door
- Extractor fans, fitted in either the kitchen or bathroom, must be used properly – in other words, close all windows and doors. This will remove moisture more effectively
- A temptation might be to switch the heating off to save money. However, heating set at a moderate temperature tends to be more cost-effective in the long run – while also guarding against condensation
- Always keep your house ventilated, even in winter time. Prevent the blocking of airbricks e.g. by outside decking
- Try not to place furniture against walls - particularly outside walls, as this prevents air from moving freely and also traps moisture
Penetrating Damp from Rain
Besides problems with roofing, such as cracked or missing tiles, the main cause of rain penetration is defective masonry:
Here is a list of some of the problems...
- Blocked & overflowing gutters
- Broken, leaking downpipes
- Running overflows from cisterns and tanks
- Porous masonry (under-fired bricks, porous stone, porous mortar)
- Cracks
- Defective pointing
- Unfilled joints and prepends
- Defective seals around doors and windows
- Holes in walls - e.g. where cables or pipes protrude
- Defective render
Properties must be properly maintained, especially the older ones. It will be cheaper, in the long run, to maintain your property rather than repair the damage caused.
Rising damp
An age-old and ubiquitous problem, rising damp is the common term for the slow upward movement of groundwater in the lower sections of walls by a process called the capillary action.
It could be that poor drainage is a contributory factor, so for starters, it’s certainly worth checking for standing water in crawlspaces and basements.
An electronic moisture meter might be used to help the diagnosis, but rising damp can also be identified by a characteristic "tide mark" on the lower section of affected walls. An experienced surveyor will use a combination of factors to diagnose the problem.
The tide mark is caused by soluble salts contained in the groundwater, which evaporates but leaves the tell-tale mark at the "peak" of the rising damp. These salts are often chloride and nitrate. They are hygroscopic and will attract water from the atmosphere.The control of salts is a very important part of damp treatments.
Damp can be halted by the presence of a damp-proof course – which is usually installed in walls to prevent groundwater rising into masonry.
In the UK, well-built modern houses include damp proofing in the form of a synthetic damp-proof course (DPC), about 15 cm above ground level, to act as a barrier through which water cannot pass.
However, a damp-proof course can be broken or incomplete, allowing moisture to cross the ‘bridge’.
Of course, the better the damp-proofing present, the less chance there is of rising damp developing. But just a few millimetres of ‘bridging’ is sufficient to cause it.
As mentioned, fighting damp is an ongoing battle. Something that cannot be understated, however, is the competence and experience of the person(s) undertaking the investigations: misdiagnosis does happen – and the costs can be high since the wrong form of treatment could be prescribed.
Please contact us if you have any queries – whether it’s about damp proofing or any of the other building services Danford, Brewer and Ives offers, such as timber treatment, condensation control, basement conversions, extensions or building maintenance.
[button style="btn-danger" url="/contact-us/" size="l" block="true" target="_self"] Contact the Damp Proofing & experts today. [/button]
Wood Rot Identification and Treatment
Damp…wood rot…they seem inevitable in a climate like ours, don’t they?
It doesn’t have to be that way: simple measures help keep both at bay. Yet if they lie undiscovered, or ignored, they can take hold. And if that happens, you might have a real problem on your hands. Timber is where damp can really take hold – in that if left untreated, it means that rot can develop. Commonly, there are two types: dry and wet rot. It comes as a result of fungi, which breed and attack wood. As a rough estimate, timber with 20 percent moisture content or higher is prone.
Common types of fungi are Serpula lacrymans (dry rot fungus); Coniophora puteana (Cellar fungus); Poria vaillantii (Pore or Mine fungus). The misleadingly-named dry rot is the enemy so far as timber preservation is concerned; it’s the most serious form of fungal decay in building timber and can destroy wood.
Wet rot is seen more often, but is less serious and usually confined to timber that stays wet. Door and window frames are common examples.
Outbreaks of dry and wet rot start similarly: when fungi introduce millions of microscopic spores into the air. If the spores fall on untreated damp wood they will germinate – via tubes called hypha which spread to form a mass of threads called mycelium. This mycelium then feeds off the wood, all the while spreading through it using hyphal threads that supply water and nutrients.
The problem is compounded, however, when the dry rot fungus spreads from infected timber onto the surface of adjacent stone or brick walls. The hyphal threads can penetrate mortar and plaster, meaning that large areas of the wall can then become infected.
The appearance of dry rot is invariably confirmed by the timber looking darker and cracked. Some wet rots, by contrast, tend to result in a bleaching appearance. While each fungus has unique features, broadly speaking they are all similar in appearance and treatments are also similar. However, because there is less mycelium it does not spread into walls – meaning that wet rot is typically confined to the area of dampness. Even so, the timber will still lose its structural integrity if left untreated.
Besides damp and rot, however, the householder might face a similar headache: the problem of insect infestation i.e. woodworm. Most commonly, this is caused by a beetle known as the Common Furniture Beetle Anobium punctatum. Exposed wood such as dead tree trunks and branches is its typical habitat, but it can also infest indoor timbers. How this happens is that adult beetles crawl out of timber in spring/summer, mate and females then return to lay eggs. Within a month, the eggs hatch and the grubs burrow into the timber for 2-4 years. Eventually, they pupate and the beetle will emerge – the process then repeating itself.
The presence of woodworm is usually indicated by the appearance of new emergence holes and a dust called frass. The beetle can infest a wide variety of wood, from structural to ornamental, but if left unchecked then structural weakening and even collapse can result in the former.
Regarding identification and timber treatment, it’s crucial that the type and cause of both wood rot and woodworm are identified before any course of action is considered.
Telling dry and wet rot apart is important, therefore, because each requires a different form of treatment. A detailed inspection should be carried out by a specialist, who will then submit a report detailing both the cause of the decay and the proposed action.
As a rule of thumb, the following (and more besides) will be investigated:
The Roof (i.e. blocked gutters, missing/broken/displaced tiles/slates).
The Walls (i.e. deterioration of mortar, faulty/missing damp proof course, blocked air bricks, cracked or broken pipes, overflow from cistern/water tank). Internally (i.e. condensation in, say, the bathroom and kitchen, moisture close to external faults, solid floors, trapped flood water, defective plumbing).
Internally (i.e. condensation in, say, the bathroom and kitchen, moisture close to external faults, solid floors, trapped flood water, defective plumbing).
Keeping on top of – or even being aware of – rot and woodworm can prove difficult, but a little time and effort can go an awfully long way. Fortunately, best practice and innovation are also moving forward, meaning that improved help and advice are readily at hand.
If in doubt, a proper timber survey is required by an expert to correctly identify the problem, the cause and the remedy which may include specialist treatment. Danford Brewer & Ives have a team of expert surveyors who can produce reports and quotations for any necessary specialist works.
If you would like more information on and detail about individual rots & wood burrowing beetles then please contact us or follow our blog as we will be covering this topic in later posts.
[button style="btn-danger" url="/contact-us/" size="l" block="true" target="_self"] Contact the Wood Rot & Timber Treatment experts today. [/button]
July's Late night opening times
Office Opening Times
Month: July 2016
Monday - 8am - 5pm
Tuesday - 8am – 5pm
Wednesday - 8am – 5pm
Thursday - 8am – 5pm
Friday - 8am – 4:30pm
Late Night Opening Hours
Monday 4 th July - 8am - 7pm
Monday 11 th July - 8am - 7pm
Monday 18 th July - 8am - 7pm
Monday 25 th July - 8am -7pm
A Quick Update...
News Round-Up: December 2015 was easily the warmest December on record, and with the heavy rainfall and flooding meant that many properties suffered from storm and flood damage. These terrible weather conditions have sent our team into overdrive to ensure our customer's properties were protected from the unprecedented weather conditions.
This extra work hasn't stopped us from carrying out contract work at Oatlands Primary School in Harrogate which involved tanking their basement which will expand the use of the property. Furthermore, we continue to build on our fantastic Timber Treatment service which has also grown over the past months.
Team News: Sadly we have had to say goodbye to Sarah who has left due to family commitments and wish her well. Luckily we have been able to find a new replacement in Amy who has settled in to the team well and has quickly and has already started providing invaluable support from the office.
Dates For Your Diary: Further to the success of our last appearance at the Listed Property Show, We are happy to announce we will be participating in the Listed Property Show at the Harrogate International Centre again this year showcasing our timber treatment solutions, basement conversion processes and damp proofing expertise. Our stand will be in a prime location in HIC and we would love you to come and say hello. The show begins on Saturday 12th March until Sunday 13th March.
Download your FREE invitation to The Listed Property Show here.
http://www.lpoc.co.uk/property-show/about-the-show/
Find directions to the show below.
HARROGATE INTERNATIONAL CENTRE (HIC) HARROGATE
BY ROAD:
From the South: Take the M1 and A1(M) before leaving at Junction 45 (Wetherby) then take the A661 to Harrogate. Alternatively, continue on the A1(M) to Junction 47 (Knaresborough) then follow the signs to Harrogate.
From the North: Take the A1(M) and exit at Junction 47 (Knaresborough) then follow the signs to Harrogate
Click here for parking information
BY RAIL:
HIC is linked to all major UK cities via Leeds or York including a direct, daily connection to London.
BY AIR:
Leeds Bradford International Airport (LBIA) is the closest airport to Harrogate.
British Airways run daily flights between Harrogate and London Heathrow and there are regular flights from many connections in Europe and worldwide, including Paris, Amsterdam, Dublin and Scandinavia.
To get from the airport to Harrogate – Catch the Airport Direct 737 bus which runs hourly and will drop you off at the bus station, then it is just a short walk from HIC.
Alternatively, there is a taxi service available with HIC just a 20-minute drive away
We hope to see you there!