Treating Damp and Water Ingress Within Historic and Listed Buildings
With many historic and listed buildings not benefiting from modern methods of damp proofing or waterproofing, they are often subject to the detrimental effects of rising and penetrating damp. The fundamental challenge when dealing with buildings of special architectural or historic interest is therefore to maintain structural and aesthetic integrity, whilst remaining sympathetic in the product application and still achieving the desired effect.
Meeting Stringent Listed Building Requirements
Nevertheless, there are products available which are ideal for treating damp in historic and listed buildings, as they meet stringent Listed Building Requirements. For instance, many Newton damp proofing products can be sympathetically applied with little or no preparation at all and depending on the chosen wall finish, often only require the very minimum of strategically placed fixings to hold the membrane in place. Once installed, the membrane achieves its design function by providing an impervious separation barrier between the damp surface and the new internal wall. Moisture and moisture vapour are prevented from affecting internal finishes, and, when supplemented by drainage, this becomes one of the most effective forms of waterproofing.
In many cases, historic brick built structures will already have been dry lined or had lime based finishes applied to mask or attempt to deal with unwelcome and unsightly staining or damp patches, visible salt deposits and exacerbated levels of internal atmospheric moisture caused by the dampness, all of which lead to continual maintenance and upkeep of the decorative wall finishes. Some wall structures such as cob or chalk actually require a relatively high level of moisture to be present in order to maintain their structural integrity. However, this can result in the detrimental effects described above. With this type of structure, there is a prerequisite to remain reasonably damp to retain structural integrity.
Problems With Chemical Damp-Proof Courses
The walls of many historical buildings are constructed with an irregular mix of materials that could not be expected to accept or sustain contemporary injected chemical damp proof courses (DPC’s). Due to the wall thickness and the sparse population of physical mass, modern, injectable chemical DPC’s do not achieve an even distribution throughout the substrate.
Even when well installed, a chemical DPC should only be seen as a damp inhibitor and not as a final solution to rising damp, and as a result of the difficulties of installing such products, many historic buildings are resigned to the idea that their walls will be damp to a degree.
Damp Proofing Above Ground Walls – Rising Damp
However, if completely dry and untainted internal wall finishes are required, there are still some products that are ideal for providing a barrier between the damp construction and internal finish. The air gap created by the studs of cuspated damp proof membranes, for example, provides an equilibrium of moisture-laden air, which maintains the natural state of the structure, helping to prolong its longevity whilst protecting the internal finishes from the damaging effects of dampness. Internally applied damp proofing membranes should be installed to at least 200mm above the highest evidence of rising dampness so as to allow the natural vapour drive to continue unimpeded through the walls above the treatment.
Damp-Proofing Above Ground Wall – Penetrating Damp
Penetrating dampness should always be treated externally at the source where the water is coming through. Water in its liquid state can only pass through a wall if there are defects large enough to accommodate it, and it is these defects that need to be repaired.
Many old walls were designed to be dampened by wind-driven rain, with the expectation that they would dry out before the moisture moved to the internal wall surface. However, persistent rain sometimes means that the moisture does reach the internal wall finishes, and shows as penetrating damp.
Specially formulated externally applied treatments will penetrate into the wall materials, blocking the capillary network and preventing moisture from entering the wall. Breathability also means that residual moisture and internal humidity can exit through the wall, resulting in damp-free internal walls that are dryer and therefore warmer, and with a dramatically reduced probability of recurring internal condensation.
Newton 807 BKK eco is an externally applied clear wall coating that penetrates into the wall materials, blocking the complex capillary network and so preventing moisture from entering the wall. BKK eco is extremely breathable and so both residual moisture and internally derived humidity are able to pass out from the wall by the process of vapour drive. Not only are the internal wall finishes free from damp, but a dry wall is a warmer wall and so the probability of internal condensation occurring is reduced dramatically.
Specialist Installation From Newton Specialist Basement Contractors
We would always recommend that the damp proofing solution is installed by a Newton Specialist Basement Contractor (NSBC) who are qualified for surveying the property, designing the best solution and installing Newton products with a full guarantee.
Treating Below Ground Areas
Subterranean areas will always be subject to penetrating damp due to the earth that bears against the structure. Water courses within permeable soil channel the water like pipes, and saturated soil develops a head of hydrostatic pressure that surrounds the subterranean structure, leading to water ingress through gaps and joints in the building fabric. To create habitable or useable areas the structure therefore needs to be waterproofed.
From a historic and listed buildings perspective, cavity drainage systems are ideally suited for below ground areas. Newton System 500 Cavity Drain Waterproofing products are ideally suited for below ground areas. When they are installed properly by Newton Specialist Basement Contractors (NSBC), they depressurise and collect water that enters the structure, removing water via gravity, if on a sloping site, or otherwise by a pumping system.
The internal finishes are isolated from the damp/water by membranes to the floor and walls leaving a dry and habitable space for the occupier, in the most demanding of situations and the most historic of structures.
Case Study: Royal Courts of Justice, London
This Grade I listed structure had a labyrinth of unused basement areas. With space at a premium, a large part of the brick basement area was converted into habitable space. Newton System 500 was quick to install and sympathetic to the structure, making it the ideal waterproofing solution.The vaults are now fully refurbished and the space used as a rest area giving a habitable area to Grade 3 of the environmental table within BS8102:2009. Following the success of this project, the Newton Specialist Basement Contractor Stonehouse Basements was commissioned to complete a second area to the same specification. Read More…
“Newton System 500 was the best solution for this project as it is deemed ‘reversible’ so meets stringent Listed Building requirements” – Graham Stone, Stonehouse Basements (Newton Specialist Basement Contractor)
Ixworth Abbey- Grade 2
British Museum- Grade 3
Douai Abbey , Berks – Grade 2
Kings College, Taunton- Grade 2
Royal York Hotel, Bath- Grade 2
Wallis House, Middlesex- Grade 2
Reform Club , London- Gade1
St Georges Hall , Liverpool- Grade 1
Menin gate, Ypres.
Houses of Parliament
Limerick Court House
Further Information and Registered Installers
For any further information about waterproofing or damp proofing a historic or listed buildings please ring 01732 360 095 or e-mail email@example.com – or fill out our online form to request a list of registered waterproofing and damp proofing contractors