Environmental Damp Control

Environmental Damp Control Services – Specialist damp and timber decay surveyors are accredited specialists & Certificated Surveyors in Remedial Treatments (C.S.R.T ) (C.T.I.S.) qualifications recognised by the Property Care Association (P.C.A) Formally known as the (BWPDA) (British Wood Preserving & Damp Proofing Association)

We offer chemical free, eco-friendly cost-effective sustainable damp control solutions. Therefore, avoiding unnecessary, costly & disruptive chemical treatments offered by many remedial damp proofing & timber treatment companies.

Need a Specialist Damp Report or a Timber Damp Survey? Call: 0800 246 5668 or Contact Us Here 

Rising dampness is widely misdiagnosed in existing properties, based on the incorrect interpretation by damp control specialists, of visual evidence and the  readings of electrical moisture meters.

Because of a highly successful sales campaign for over many years by specialist damp control companies & contractors installing injected ‘chemical damp-proof courses’, this misdiagnosis of rising dampness by these damp control companies has also become synonymous with a diagnosis of a lack of an ‘injected chemical damp-proof course’.

Although this has been very good for damp control companies & damp-proofing contractors, it has often resulted in a waste of the clients’ money and resources; original plasters and finishes have been destroyed in the process of installation, and unnecessary damage has been caused by damp control companies, to original  brickwork & stone structures by the drilling of irrigation holes by damp control specialists. In addition, money that might have been spent on more cost-effective maintenance or other essential specialist repairs has been wasted.

Building Surveyors, who carry out surveys & inspections for Building Societies or homeowners, will check for dampness using an electrical conductance moisture meter most commonly manufactured by “Protimeter”. Electrical moisture meters can only be used to accurately assess the level of moisture in timber as this is the primary task they were designed for.

When used in other materials it can only record the presence of surface moisture and is unable to determine the true moisture content existing below the surface, i.e. within the wall. High readings ( often mis-diagnosed as dampness) can also be obtained from plasters containing black ask mortar and also foil-backed wallpaper so the you should be wary of any surveyor or damp-proofing company relying solely on the use of moisture meters.
 
A Chartered Surveyor is therefore only able to detect surface moisture, and will often report: “there is evidence of dampness and remedial damp-proofing work in this respect is required”. Alternatively: “you need to instruct a PCA registered damp-proofing and timber treatment contractor to carry out a full investigation to investigate the full extent of the problem and to carryout any necessary repairs, together with an estimate for any damp-proofing and timber treatments.”
 
DAMP CONTROL, A common example showing the effect of inserting a damp-proof material into a structure is the sudden appearance of ‘rising damp’ in walls after the laying of a new concrete floor incorporating a damp-proof membrane. (Usually when a suspended timber floor has been replaced with solid or when a breathable stone slab floor is lifted and re-laid with a damp-proof membrane below).

The original substrate below the timber floor or breathable solid floor would have allowed moisture to evaporate off the large surface without affecting the internal walls and finishes. However, with the introduction of an impermeable membrane, the elevated moisture levels accumulate beneath and is forced out to the sides and into the base of the walls. This will cause damp and timber decay problems to occur in a house unless suitable ventilation is provided at the floor/wall junction.

If it is decided that a moisture barrier is essential at the base of the walls, then the most dependable technique would be to introduce a physical barrier rather than a chemical one. This method would involve the ‘cutting-in’ of a layer of damp-proof material to form a continuous barrier with the damp-proof membrane under the floor. As the wall above this barrier will remain damp for some time, it is essential that susceptible materials (i.e. skirting boards) above as well as below the barrier are isolated from the base of the wall with a damp-proof membrane or ventilation air gap

A damp-proof barrier is always susceptible to localised failure resulting in concentrated moisture and damp at these points. (This is a general characteristic of all impermeable materials which are generally found to fail at some point). Because of this, traditional building techniques rely upon the use of permeable materials and ventilation systems to disperse moisture and prevent it coming into contact with susceptible materials and internal surfaces.

‘Chemical damp-proofing’ may provide a useful barrier in controlling rising dampness in the short to medium term, however, any gaps which are left, or which appear over time as the building material weakens, may lead to damp ingress and possible timber decay to walls & floors in houses.

DAMP CONTROL SERVICES FOR GROUND WATER/ DRAINAGE AROUND BUILDINGS

Ground drainage is the most cost-effective environmental dampness control method of controlling rising dampness & timber decay in old buildings, including that which results in damp masonry at the lower part of the wall. Reducing moisture sources and providing adequate passive moisture sinks to disperse any penetrative moisture will make the system fail-safe.

This should start with the provision of sufficient ground drainage around the building, thus minimising water penetration and controlling rising damp to the foundations, and the re-routing of surface drainage away from the base of the walls. The ‘French drain’ system has become fashionable to help with this process. This consists of a channel dug along the base of the wall and filled with shingle. However, these often become blocked with debris and soil which prevents proper moisture drainage and evaporation from the foot of the wall. A more traditional method used in the UK, is to provide a ventilated and drained ‘dry area’ around the base of the wall, which are generally enclosed with flag stone slabs thus preventing debris accumulating in the drained dry area and therefore reducing maintenance. When providing the latter system, the flag stones MUST be a minimum of 150 mm below the damp-proof course level.

 DAMP CONTROL SERVICES, DAMPNESS ENTRAPPED IN BUILDINGS

The use of dense finishes, such as sand/cement renders, around the base of external elevation of walls is a regular cause of damp problems. These finished prevent moisture evaporating from the base of the wall; instead the moisture is forced into the internal walls surface, where evaporation takes place, and leads to decorative spoiling and timber decay.

As with all impermeable materials they will eventually break down with age, allowing water seepage into the base of the walls, but preventing evaporation and drying of the wall to take place. Using a more traditional ‘breathable’ renovating lime mortar and the correct finish of external renders projecting water away from the base of the wall, thus preventing the bridging of any existing damp-proof course system, would be the desired solutions.

Providing that a Cavity wall construction is through ventilated, it may provide a way of dispersing moisture and prevent it penetrating through onto the internal surface of a building. If debris, or the ill-advised injection of insulation foams, fills the cavity, bridging of the existing damp-proof course may occur allowing water to penetrate through to the interior surface and lead to the spoiling of decorative surfaces or timber decay. Sometimes, the most cost-effective solution would be to re-establish a through-ventilated cavity.

In general, the breakdown of an existing damp-proof course usually results from the bridging by incorrect repairs and alterations, raised ground levels, localised damage due to structural movement or poor building maintenance.

If a damp-proof course is an original design (i.e. physical damp proof course) to control moisture movement in the structure, it may be necessary to carry out local repairs. Ideally this is best done by ‘cutting in’ a new layer of damp-proof material locally, however this is the more time consuming, disruptive and therefore the more expensive method.

ENVIRONMENTAL DAMP CONTROL SERVICES IN BUILDINGS USING VENTILATION 

Conventionally, buildings which are built on damp or potentially damp sites generally include sub-floor through ventilation cavities, basements / cellars. These areas act as sumps to allow the evaporation and dispersal of moisture ingress from the structure before it extends to occupied areas or susceptible decorative finishes.

If the sub floor ventilation of basements, cellars or sub-floor cavities is restricted, moisture will build up and penetrate susceptible structures increasing the risk of dampness and other sub floor ventilation problems, such as timber decay to joists, & wood boring beetle infestations.

This can arise for example by soil/plants or raised ground levels blocking up the sub-floor air bricks or by the application of waterproofing materials. The solution to these problems would be to use environmental dampness control methods which will increase the ventilation still further, not to start applying further waterproofing materials to the substrate.

As mentioned earlier, the re-in-statement of a through-ventilated suspended timber floor is generally preferable to the replacement with a solid concrete floor. The requirement for continual dispersal of dampness should not impede the use of basements and cellars as occupied areas, however the walls should be kept well ventilated and not sealed.

This can be achieved by using a through-ventilated dry lining system rather than an impermeable finish or a rendered tanking system, which would force moisture into adjacent structures to the side or above.

Traditionally, ‘dry lining’ has been applied by using timber panelling, isolated from the masonry with timber battens or the use of lath and plaster. In such cases, the void behind must be ventilated at the top and bottom thus allowing through-ventilation to occur and aid in the evaporation of moisture.

Failure to supply this ventilation will lead to the build-up of moisture causing damp and timber decay to occur. This commonly happens when insulation material or building debris is allowed to block the cavity behind lath and plaster, or when numerous layers of paint accumulate over timber panelling.

By using timber panelling to dado level, this can provide an attractive and cost-effective answer to problems of penetrating damp or condensation affecting the lower levels of masonry walls.  Modern materials and techniques may be used to achieve the same goal, and many environmental damp control systems & products are available on the market to allow the cost-effective provision of through-ventilated dry lining systems, including specialist plasterboard systems and plastic ‘cavity drainage’ membranes.

Once a damp survey and a report is completed the causes of any damp problems in a building will be apparent.  To prevent dampness from worsening immediate actions should be initiated to prevent further moisture ingress to the structure of the building and to increase ventilation within the affected areas of damp.  These two actions alone can be used to ‘mothball’ a building which, for whatever reason, cannot undergo full damp-proofing remedial repairs.

‘Mothballing’ essentially entails instigating systems that will minimise further water loading of the suspect areas of the building and at the same time improving the rate of drying of damp areas.  A range of different types of techniques can be used for example:  1. correcting all defects in rainwater systems (i.e. clearing out gutters, making temporary repairs to valleys and providing suitable overflows etc.), 2. correcting other building defects which allow water penetration, for example defects in lead work and inadequately pointed stonework, defective windows and their pointing.  3.  Unblocking chimneys and re-capping thus allowing ventilation of flues, unblocking any external ventilation systems, opening up fireplaces.  4. Increasing underfloor and general building cavity ventilation by opening up sub-floor airways, removing single floorboards next to walls, making slots in walls at ceiling and floor level, installing hatches into ceiling voids. 5 Checking ventilation in roof voids and encouraging through (or cross) ventilation where appropriate by the installation of roof vents or adapting the construction of eaves.  6. Removing floor coverings and moving clutter away from walls.  7. Exposing internal down pipes, checking for water tightness and repairing as necessary or diverting water streams away from walls into suitable moisture sinks.

When it comes to protecting your property against rising dampness & timber decay and any other form of dampness found in a house our damp & timber decay specialist are right there with you and have been for nearly 30 years.  

Our in-depth damp surveys will correctly diagnose any damp wall issue be it failed damp-course or damp-proof course been bridged, which can lead to water ingress to walls causing penetrating damp and condensation.  

This is where accurate diagnosis is imperative so that the appropriate damp control treatments are used thus avoiding the cost of having another chemical injected damp-proof course installed in the walls of your house, flat or any other property.

Damp control Services, diagnosing damp & timber decay problems – what signs to look for

Your first step in fixing dampness is to find the main source. There are many different types of dampness – here are the signs you should be looking out for.

 DAMP CONTROL SERVICES, RISING DAMP

Rising damp is caused by a non-existent or faulty damp proof course and describes the action of groundwater moving up through a wall through capillary action. Due to the nature of rising damp, only your ground floor will be affected by this type of damp. Signs of rising damp include:

• A noticeable tidemark on an interior wall up to 1.5m
• Peeling or flaking skirting boards
• Blistering plaster or paint
• White powder on walls (salts)

DAMP CONTROL,PENERTRATING DAMPNESS

Penetrating damp, otherwise referred to as water ingress, means that water is making its way into your home from the outside. This can occur in a number of ways, either via a burst pipe, leaky roof, or damaged masonry. Common signs of penetrating damp include:

• Localised damp patches on walls or ceiling
• Damp that becomes more visible when it rains
• Moss or algae growth on external wall
• Damaged brickwork
• Damaged guttering and down pipes

CONDENSATION

Condensation is caused by poor ventilation and is the most common type of damp to affect UK homes. Condensation mostly occurring during the winter when the difference between external and internal temperatures is most dramatic. Signs of condensation problem include:

• Fogging on windows
• Black mould growth on windowsills, walls or even furniture
• Smell of mildew
• Blistering paint
• Peeling wallpaper

TIMBER ROT

It is important to catch timber rot before it has time to develop. Dry rot in particular spreads very easily throughout a property and weakens rafters and floorboards over time, to the point that they will eventually become unsafe. Dry rot and wet rot affect your timbers in different ways:

DRY ROT

• Damp, fungal mushroom smell
• Affected timber feels brittle and warped
• Deep cracks in the wood – often in a ‘cube’ formation
• Evidence of mycelium growth on timbers (white fluffy coating)
• Large fruiting bodies

WET ROT

• Affected timber feels wet and spongy
• Affected timber will appear darker
• Easy to crumble
• Damp, musty odour
• Look out for black fungus growth

Contact our independent timber and damp control experts today!

If you have already identified your damp problem, great! Our independent damp experts can offer environmentally friendly cost effective damp solutions. If you need further help with identifying the cause of damp in your home, then we can carry out a professional damp survey to provide the answers you need to get started on repairs.

If you require a damp and timber decay survey /report on a house or flat to satisfy your mortgage loan provider or yourself, call direct 0800 246 56 68  alternatively to arrange a survey please fill in our contact form

Damp survey, timber survey for house purchase, combined damp and timber survey, specialist timber and damp reports for mortgage providers, damp-proofing quotation and woodworm treatment are provided by Adept UK Damp & Decay in the following North West, Midlands and South East regions / areas.

Birmingham damp & timber survey, Cheshire damp & timber survey, Chester damp & timber survey, Lancashire damp & timber survey, Liverpool damp & timber survey, London damp &  timber survey, Manchester damp & timber survey, North West damp & timber survey, North Wales damp & timber survey, Shropshire damp & timber survey, West Midlands damp & timber survey, & Wirral damp & timber survey.