DampAid UK
Damp Proofing, Woodworm, Dry Rot & Wet Rot Specialists
Consultants & Specialist.
Damp and Timber Survey, Report, Control & Treatment.
Damp-proofing, Rising Damp, Woodworm. Dry Rot & Timber / Fungal Decay
Damp proofing ~ Woodworm Treatment ~ Rising Damp ~ Damp Proof Course ~ Dry Rot Treatment ~ Wet Rot Treatment ~ Property Care Specialists
DAMP AND TIMBER REPORT JARGON BUSTER
When instructing a surveyor to carry out a survey on a building, whether it be in the case of a pre-purchase, re-mortgage or for rising damp, woodworm or dry rot, you will inevitably, after the survey has been carried out, receive a report from the surveyor. This will detail the construction, condition, and any defects found. Whether it's a building survey or a damp and timber survey, the report will state the obvious, but will also use terms which you may find confusing. Phrases such as "timbers in contact with damp masonry may be at risk to timber decay" or even terms such as purlins, rendering & dpc mean nothing to some people. We have come across lots of clients who have been confused by some terms used by the surveyor in his report and others who are wondering "what in the world does that mean?"!! This web page has been designed to help you cut through the jargon. For any further advice please feel free to contact Damp Aid (at no cost to yourself) on 0800 0680 881 or via email on our contacts page.
Air brick
A perforated brick or grate built into a wall, to provide ventilation below a suspended floor to prevent fungal decay i.e. dry rot & wet rot and attack by wood boring insects.
BBA
The British Board of Agrement certifies the quality of building materials, including damp proofing and timber treatment products.
Bell Drip
Angled section at bottom of a rendered wall which allows rainwater to drip off slightly away from the base of the main walls thus preventing bridging of the damp proof course and penetrating damp.
BRE
Building Research Establishment - The BRE Trust Companies, BRE and BRE Global, are world leading research, consultancy, training, testing and certification organisations delivering sustainability and innovation across the built environment and beyond.
BSI
The British Standards Institute administers 'Kitemark' licences relating to a very wide range of goods, materials and systems used in all areas of the construction industry. For example, BS 6576 sets out a code of practice for installing chemical damp proof courses. The BSI also administers the ISO 9000 series of quality management standards. For more information contact BSI, 389 Chiswick High Road, London W4 4AL
Building Survey
This is a far more detailed survey formerly known as a 'Structural Survey'. The report will give a detailed account of any property defects and the best course of action to rectify the problems. It will also give advice on matters that may become a future issue. This can cost anything from £500 - £4,000 depending on the value of the property.
Whilst surveyors will be able to identify and determine the cause of any problems, further specialist advice is usually recommended to obtain estimate for remedial repairs or to obtain access to areas that could not be seen during the surveyor's inspection e.g. at roof level. In the event of a survey highlighting areas of concern, we would strongly recommend you obtain the opinion of a specialist before deciding on which course of action to take. Some of the more common problems are: Structural issues, problems relating to the roof, potential damp and timber defects.
BWPDA
British Wood Preserving & Damp-proofing Association. See PCA below for more details.
Cavity Wall
A main, external, wall built of two leaves of brick, stone or a type of block, and a space in between. Normally the inner leaf is load bearing and the function of the outer leaf is to protect the inner leaf from the weather, the two leaves are linked by ties, normally of metal. A cavity wall is usually more resistant to damp penetration than a solid wall, and has greater thermal insulation.
Ceramic Tubes
See Syphon system below
Chemical injection Damp proof course
Chemical damp-proof courses are inserted to control the vertical passage of moisture from the ground, and are almost all installed in properties where no damp proof course exists or it has broken down with age.
Condensation
This is caused by high humidity (moisture in the air) within a property. It differs from rising and penetrating damp in that it is caused by excessive moisture within the property that cannot escape, rather that damp coming in.
The most tell tale sign of condensation is mould growth which can be black, white, yellow or green.
The first sign that condensation is a problem is when black pinpricks of mould appear on walls, ceilings or even furnishings. There is usually a musty smell and clothes and shoes in cupboards can become covered in a white or green furry mould. Factors which contribute to condensation include moisture produced from bathrooms, kitchens, drying clothes indoors, paraffin/flue less heaters and insufficient ventilation. If the cause of condensation is not rectified, the mould will grow and can eventually cover whole walls and ceilings and ruin clothes and decorations.
Coping Stone
Brick or stonework on top of a wall, to stop damp penetrating the top of the wall.
Damp and Timber Specialist Survey & Report
A timber and damp specialist survey will identify any areas of rising or penetrating damp or timber defects. The cost of an inspection and report is usually fairly minor. The fees for these surveys are usually refundable if the company is subsequently instructed to carry out the required repairs.
Damp-proof course (DPC)
Often abbreviated as DPC. A layer of impermeable material built into a wall to prevent damp rising within it. Older damp proof courses are often of slates; more recently felt impregnated with bitumen; modern construction uses heavy duty polythene. A chemical damp proof course can be injected into an old wall, forming an impermeable layer within the masonry, although its efficiency varies with the type of construction. A vertical damp proof course is required to keep a room below ground level dry(known as tanking), or where a horizontal damp prood course may be bridged. Damp proof courses are also installed in other parts of a structure.
Damp-proof membrane (DPM)
A sheet DPC underneath a solid floor to keep the surface dry.
Diffusion System
A concentrated silane/siloxane 'cream' which is slowly diffused into the masonry. When it reacts with the silica in the masonry it forms a water repellent barrier.
Dry Rot
The true Dry Rot fungus (Latin name Serpula lacrymans) is the more serious of the wood destroying fungi. It causes extensive damage to structural timbers if not treated in time. It will spread undetected behind wall plaster and even through thick walls in search of timber to attack. Timber affected by dry rot is brown, dry and brittle with cube shaped (cuboidal) fractures and can be crumbled by hand. The fruiting body (or fungus/mushroom growth) gives off millions of spores which resembles red dust and is often mistaken for brick dust
Dutch or Holland System
See syphon system below
Efflorescence
Salts brought to the surface when moisture evaporates from the surface of brickwork or plaster.
Electro Osmosis
This is an active system which introduces an electrical current into the wall just above the ground level. It involves the insertion of a continuous titanium band into the mortar joint along with electrodes positioned at intervals. The current repels rising moisture back down the wall. As long as the charge is maintained the walls will remain dry and free of damp.
Exchange of Contracts
Once the contract has been signed by both parties and you have transferred the deposit to your solicitor (normally 10% of the purchase price), your solicitor should be getting close to being ready to exchange contracts. You will normally need to have agreed on a completion date with the seller prior to exchange of contracts. This is done either directly or more usually via the solicitors or estate agents. At exchange of contracts the purchase becomes legally binding. If either party were to pull out of the transaction at this time, there are likely to be heavy financial implications for the person that withdraws from the sale.
External ground lowering
Carried out where external ground level is bridging the damp proof course.
Fungal Decay
The infection of timber by wood-destroying fungi such as Wet rot and Dry Rot. (see timber decay below)
Flashings
Strips of (usually) lead fixed to waterproof a joint, eg between a roof and a wall, or at the base of a chimney stack.
Flaunching
Cement work at the top of chimney stacks securing the terminal pot.
GPI (formerly GPT & GPIC)
Guarantee Protection Insurance Ltd. - Provides specialist insurance to cover Rising damp (damp proofing), woodworm treatment, dry rot treatment & wet rot treatment. (37 Carrick Street, Ayr, Ayrshire, Scotland KA7 1NS)
Holland Damp proofing system
see Syphon system below
Homebuyer Report
A Homebuyer Report covers the same issues as a Building Survey, but in less detail. The report should include a brief description of any defects and where necessary will indicate what should be done to rectify any problems. A Homebuyer Report includes a valuation of the property for the client's use whereas the Building Survey does not. This report should cost between £300 - £1,000 and is usually based on the value of the property.
Hygroscopic Salts
Hygroscopic means "the ability to absorb moisture from the surrounding environment". The salts (Chlorides and nitrates) which originate in the soil, are transported with damp as it rises through masonry. Hygroscopic salts can cause walls to remain damp even if there is no source of water ingress.
IWSc
Institue of Wood Science - The purpose of the Institute of Wood Science is to advance and encourage the scientific, technical, practical and general knowledge of timber and wood based materials.
Joist
Horizontal timbers supporting floors or roof structure.
Lintel
A beam, normally of timber concrete, steel or stone, spanning a window or door opening.
Masonry
Brickwork, stonework or blockwork.
Mastic
A generic term used for flexible sealant, e.g. around window openings.
Mortgage Offer
Once your lender has made all the relevant checks, they will issue a mortgage offer, which is a document setting out the details of the mortgage. You will receive one copy, whilst another will go to your solicitor. Assuming everything is in order and you sign the offer, the morgage is effectively in place.
Parapet
A wall built up above roof level.
Parquet floor
Small strips of hardwood laid in an interlocking pattern on a solid floor.
Party Wall
A wall separating, and shared by, adjoining properties.
Penetrating damp
Penetrating Damp is caused by moisture penetrating through the roof or walls. Causes include: defective pointing/flashings, faulty rainwater goods, defective roof coverings, plumbing leaks, defects around window joinery and doors, and many more.
Such defects generally cause localized problems and readily become evident in the form of damp patches appearing.
Pointing
the neat finishing or mortar joints in masonry
PCA (formerly BWPDA)
Property Care Association - The PCA is the premier trade body representing specialists in structural waterproofing, damp proofing, wood preservation, structural maintenance & flooding
Purlin
a large horizontal timber, part of the roof structure, supporting the rafters, and normally supported by load bearing walls.
Rafters
A sloping timber, part of the roof structure, supporting the tile or slate battens and probably resting on purlins.
Rainwater Goods
Properties guttering and down pipes.
Rendering
The sand/cement finish to an external wall, or the first coat in plastering.
Ridge
The horizontal top of a pitched roof.
Rising damp
Rising damp is a condition caused by ground moisture rising up a masonry wall by capillary action. It occurs where there is no damp-proof course or where the damp-proof course has been damaged or bridged. Where present, moisture can rise up the wall to an average height of approx 1.2 metres and it can sometimes leave a characteristic horizontal 'tide mark'.
Schjriver System
See Syphon system below
Silicone treatment
Weathering and frost damage of masonry can be reduced by spraying with silicone-based liquid thus preventing penetrating damp.
Structural Survey
See Building Survey above.
Syphon System (also spelled Siphon)
Over the years there have been various designs/names connected with this type of system, the latest being the Holland Damp Poofing System. They have stated that by intalling these systems, (which will probably cost you £2,000) then your rising damp will be cured and prevented. Do not be fooled!! They do not provide a damp proof course or prevent rising damp. (see further information here - reproduced with permission of the PCA - all copyright reserved)
Timber decay
Timber decay occurs in timber which becomes wet and is attacked by one of a number of wood-destroying fungi. It always arises because the wood has become wet (above 20% moisture content). Finding the source of dampness and eliminating the ingress of moisture is always necessary. (see fungal decay above).
Valuation Survey
When you formally apply for your mortgage, they will arrange a basic valuation report, to check that the property is worth enough to support the amount you want to borrow. The fees for valuations are generally set by the lender. This report does not go into any real detail on the state of the property, so you may want to instruct a surveyor to carry out a more detailed inspection for your own peace of mind. There are two types to choose from: Homebuyer report & Building Survey. (See details under relevant headings).
Vapour barrier
An impermeable layer, often of polythene, fixed to prevent condensation and possible rot within a timber structure.
Wall plate
A timber along a wall top, to carry floor joists or rafters.
Weather board
A board fixed at the bottom of a door, or door opening, to prevent rainwater driving in.
Weepholes
Small holes left in a wall to allow moisture to drain out.
Wet Rot
Wet rot is a wood destroying fungus and is a common cause of structural timber defects. It requires a moisture content of 50 to 60% to survive. It does not spread through masonry and growth will stop when the source of moisture is removed.
Timber affected by wet rot darkens, with cracks running along the grain of the wood and minor cracks appearing across the grain. These are usually less deep than those caused by dry rot.
Woodworm (Wood Boring Beetles)
A type of timber infestation in which grubs eat their way along, and weaken timbers before flying away from a flight hole. There are various varieties of worm attack, for example - Common Furniture Beetle, Death Watch Beetle, House Longhorn Beetle.