Introducing a live renovation
Build It expert, Alan Tierney, talks us through his refurb of a grade II* listed property in Devon
Alan Tierney embarks on his own ambitious refurb project
As many Build It readers will know, I’ve worked as a historic building consultant for the past 15 years. In that period, I have advised many clients on how to repair and renovate old properties. I’ve now decided the time has come to put my money where my mouth is and take on a restoration project of my own!
I’ve purchased a grade II* listed house in Devon, which needs a complete overhaul. Though it’s generally in good structural condition, most of the dwelling has no electricity, heating or plumbing. Like many old buildings, it was subject to various alterations in the 20th century, using materials incompatible with its traditional construction. Plus, the quality of some of that work leaves a lot to be desired.
This is a long-term project that’ll take years to complete. As it progresses, I’ll be writing a blog for Build It, which you can read online at www.self-build.co.uk/alan-blog. I look forward to having you with me on the journey.
The house’s history
The building is constructed of stone on the ground floor and cob on the first storey, with a thatched roof covering. This is typical for this part of Devon. In fact, all the materials are very local – the clay for the cob and some of the stone were even dug from the site itself.
The property’s development is quite complex and is not easy to date accurately, but it was clearly constructed one section at a time over several hundred years. The oldest part is the eastern portion of the main structure, dating from the mid 16th century. This accommodates a dining room and bedroom. It is nearest to the centre of the village and adjoins older houses in a terrace. We’re not sure what happened next, but the rest of the main structure was built some time during the 17th and 18th centuries. Work likely took place in two phases, with a massive chimney stack and staircases incorporated. In the 19th century a rear wing was added to house a kitchen and a bedroom.
In the 1970s or 80s a single storey extension was added to the back of the property, establishing a garden room and store. This is in appalling condition and will have to be replaced. Finally, in the 1990s some outbuildings attached to the 19th century wing were converted into an independent annexe. The quality of construction and the dated design leaves a lot to be desired and will need considerable alteration in due course. For now, though, it provides very comfortable accommodation while we carry out the work on the main structure. It’s a major bonus – I refer to it as the world’s most comfortable site caravan.
Assessing the condition
The older parts of the house are in a good state of repair including, thankfully, the thatch. This is despite extensive incorporation of inappropriate, cement-based materials such as solid concrete floors, cementitious plaster and Artex to the ground floor. Sand and cement render has been applied externally to the first storey cob and cement pointing to the stonework on ground level. These are interfering with the ability of the historic fabric to dry out, making the house cold and uncomfortable. We’re lucky it has endured these interventions relatively unscathed.
Its survival is due to a combination of factors. Firstly, we are on top of a hill, so the site is well drained – even in rainy
Devon. The large overhang from the thatched roof protects the first-floor render from the elements, too. The stone walls of the ground floor, up to 800mm thick, are very resilient. Though they are damp in places, they show few signs of deterioration.
Poor quality metal windows were fitted in the 80s and are very draughty. They’re unsightly and have bad thermal performance – but do, at least, mean the home has been well ventilated. Plus, the main dwelling has been largely empty for much of the past 20-25 years, without any central heating. As a result, the amount of water vapour that has been generated internally is much lower than it would be in an occupied building.
The annexe is poorly designed and constructed. While the stone walls surviving from the earlier outbuildings are in good condition, poor quality timber in windows, doors, etc has deteriorated and the new blockwork gable wall is showing signs of structural failure.
The single-storey garden room extension is a disaster area. The roof leaks in numerous places, the walls are severely damp, window frames are rotten, roof timbers are decayed – the list goes on. It’s a sadly common and rather chastening experience to see a modern part of the building at the point of total failure within 40 years of construction, while the adjoining part is still going strong after 450 years, despite everything that’s been thrown at it.
Our renovation objectives
We have three clear goals for the project. Firstly, to conserve this important historic building – only about 5% of listed buildings have grade II* status. Secondly, we’d like to create a comfortable, attractive and healthy home for the long-term. We are also keen to maximise sustainability throughout the scheme, both in terms of execution and how the property operates in the future.
Fortunately, these aims are compatible with one another and have considerable overlap. The best materials for use in traditional buildings are natural ones. These generally come with good sustainability credentials and are ideal for creating comfortable, healthy living environments. The decisions we take throughout the scheme will need to satisfy all three aims. We’re in the process of compiling a team to work on the project, and their commitment to this philosophy will be an essential qualification.
Our plans for the internal plasterwork, for instance, illustrate this approach. Clay plaster is a historically appropriate material for this kind of structure. It is highly vapour permeable and has functional physical properties that are extremely beneficial to traditional building fabric. Those characteristics include the ability to buffer moisture and temperature, establishing a healthy living environment. The soft finish and flowing lines of this solution enhance the character of an old dwelling, too, and create an attractive aesthetic for modern living.
We are fortunate to have a paddock from which we will dig the clay to make plaster, eliminating any environmental cost from manufacture or transportation. The excavation of the raw material will serve a dual purpose, forming trenches for the installation of a ground source heat pump (GSHP). Clay plaster is also durable, infinitely reusable and recyclable, so is sustainably future proof.
Renovating in stages
The first phase of the project will be to strip back the modern finishes and remove the solid concrete floors, to be replaced with lime surfaces bedded on foamed glass aggregate. When the building is uncovered we will be able to carry out first fix electrics and plumbing, including pipework for underfloor heating. Alongside this will be the design process for windows, doors and a staircase, as well as the replacement of the garden room with a glazed, light-filled atrium. We will also reconfigure the annexe. These alterations will require a series of listed building consent applications – the first of which has already been submitted for consideration.
During the summers we will do the external work, which includes raking out the cement pointing and redoing it with lime. We will also add a new ridge to the thatch and carry out some minor repairs, excavate the clay for the GSHP and strip the cement render, ready for its lime replacement.
Once the new windows have been fitted and the lime floors have cured, we will replaster and repair the surviving historic plaster finishes, most of which are upstairs. Some of the modern partitions and subdivisions will also be reconfigured. At this point, we will carry out joinery repairs and install the new staircase, too.
Of course, that’s just for starters. There’s lots to do, so there needs to be a balance between what I can realistically do myself, using my existing skills and developing some new ones, and what it’s more sensible to engage other skilled professionals for. Follow our project online at www.self-build.co.uk/alan-blog to see how we get on.