Fitness for human habitation act.

we will look at each of these groups and consider whether the cause is likely to derive from condition and design of the building itself or from the activities of the inhabitants.
Structural damp

This category covers dampness that penetrates into the structure of the building, either from the ground or from rainwater. Examples include rising damp, rain penetration, groundwater penetration into basements and leaking roofs.
Most structural damp issues occur due to lack of maintenance, poor detailing when buildings have been extended or modified or from buildings being poorly designed in the first place. For this reason, in most cases, it is reasonable to say that it is the responsibility of the landlord to ensure that this type of dampness is dealt with.
Unfortunately there are a multitude of routes through which rainwater or groundwater can enter a building, especially in the case of older solid-walled buildings such as those from the Victorian era. Examples include:
Lack of a damp-proof course
Porous masonry – i.e. under-fired bricks, porous stone or porous mortar
Defective pointing
Unfilled joints and perpends
Defective seals around doors and windows
Holes in walls – e.g. where cables or pipes protrude
Defective render
Missing tiles
Defective guttering

With all of these examples, prevention is normally better than cure and it is a good idea to try and deal with them at the same time as carrying out other works to a building, in order to minimise costs. For example, if you are replastering a room in a building that doesn’t have a damp-proof course (DPC), installing a new DPC using Dryrod Damp-Proofing Rods at the same time is a simple and cost-effective intervention compared with having to deal with a rising damp issue in the future.
Likewise, when a building is scaffolded for painting, always take the opportunity to look at the condition of the external walls and carry out any necessary repairs.
As a second line of defence, consider the use of damp resistant plastering systems on internal walls. Standard gypsum-based plasters are very susceptible to moisture damage, but specialist plastering systems are now available that are specifically designed to resist dampness.
Escape of Water
Dampness caused by escape of water most commonly derives from leaking plumbing or appliances – typically:

Water tanks
Water pipes
Central heating
Domestic appliances such as washing machines or dishwashers
Ascertaining whether fault lies with the landlord or tenant requires the use of a bit of common sense. Generally, if the fault has occurred due to lack of maintenance, the fault will lie with the landlord. In many cases, damage caused by escape of water will be covered under home insurance policies.
Condensation & Mould

Dampness caused by condensation, and the resulting mould problems, are likely to be the most contentious issue raised by the new Act.
There are a number of factors that contribute towards condensation risk in buildings, some of which are likely to be regarded as the responsibility of the landlord. However, tenant behavior also plays a major role.
Condensation occurs when moisture-laden air comes into contact with cold surfaces, causing the moisture within the air to condense into liquid water. Although it is a problem in its own right, it is the resultant mould growth that tends to cause the most concern.
Due to their inherent design, some buildings are more susceptible to condensation issues than others and it can even affect modern buildings. Landlords can help minimise the risk of condensation by ensuring that walls are well insulated, as increased wall surface temperatures mean that condensation is less likely to occur. Supplying adequate ventilation is also essential, as it replaces moisture-laden air from inside the building with air from outside the building, which is actually drier throughout most of the year.

However, for condensation problems to be resolved, a certain degree of co-operation from the occupants of a building will usually be required. Insulation measures will be of little use if tenants do not heat a building at all, which, sadly, is a common occurrence due to fuel poverty. Mechanical ventilation systems are also of little use if tenants turn them off, due to concerns about running costs or noise.
For these reasons, it is sometimes necessary to treat the symptoms rather than the cause and use fungicidal washes and fungicidal paints. These don’t deal with the condensation itself, but will help alleviate the resultant mould growth, which is what is usually the primary concern of the tenant