The existing challenge – the builder’s tale

Third in a series of posts on the ambitious refurbishment of a Hackney Victorian house. This time it’s the turn of the builder Dave Manby to tell his side of the story.. after he recounts tales of white water rafting

Rowing the 18ft S.O.T.A.R raft through Granite rapid

Around two years ago my sister Bron and her partner Rob bought 89 Culford Road, and I was told I was going to do the building work on the house — once they had appointed an architect, decided just what they wanted to do with the house, decided how far to take the green refurbishment and sorted out the planning permission. In due time and without any real great haste as far as I could gather Bob Prewett was appointed as the architect and Bron and Rob instructed him on a “no compromise” refurbishment.

Patient build-up Sitting on the sidelines, getting the occasional update from my sister and from my 30+ year’s experience of building works in and around London I knew that the proposed plans were never going to be an easy planning application to get approved by Hackney (or any other council) and that the De Beauvoir owners’ association would object to a change of even the letter box. Also I did find “the clients’” slowness of decision making worrying for future “build decisions” and their surprise at the missed deadlines by Hackney a little perplexing.  So I did not drop all my other work in readiness for the refurbishment — but I did worry about having to tell my sister that there would be a month of no work whilst I went off to row a raft down the Grand Canyon with a group of friends in June 2008.

Fast forward to November 2008, and after a very enjoyable Grand Canyon trip I start work on some trial pits and demolition of the old rear extensions whilst waiting for the party wall agreement to be signed “imminently”. Imminently obviously has different meaning in surveyors’ language and so I closed the site down from 13th November till 5th January.

Finally 5th January of this year comes, and the party wall agreements still are not signed, and I have another week off work.  So I start editing film from an Iranian kayak expedition I did a few years ago and Pete and Mickey pick up a couple of small jobs. Bob the architect keeps saying that we are not your average builders!

5th January of this year comes, and the party wall agreements still are not signed, and I have another week off work.  So I start editing film from an Iranian kayak expedition… Bob the architect keeps saying that we are not your average builders

The beginning, at last 12th January and finally, finally we can start real work. The build specification requires steels to be mounted on spreader plates in the party walls, to hold the new ceiling and floor joists. This way, there are no joists mounted in the external front wall and a continuous wall of insulation with no air leakage or cold bridges can be inserted between the steels and the wall. I told you it was a “no compromise” energy saving design.  Also new steels have to be placed in the middle and rear of the building to hold the new roof and roof room. These steels enable me to take the house down while leaving the old roof in place, so we can work in the rain and the party walls are kept dry. And so from the middle of January till the middle of March we demolished the interior and the rear wall of the house, storing the old floor boards for re-use in the rafters as we came down floor by floor.

Bad bricks Then we discovered the state of the old brickwork. If anyone says to me “Oh but they don’t build houses like they used to”, implying that modern building standards and methods are poor, then they have never seen old houses stripped back Victorian and Georgian builders built terribly, and the good ones are the ones that are still standing! 89 Culford Road turns out to be the worst built house that I have ever worked on; funny given the value of the property in the neighbourhood. The rear wall was built in two skins: the interior built using all the broken bits of brick lying around; and the exterior built using face bricks, but with very few header bricks — just snap headers to make it look like a proper build.

If anyone says to me “Oh but they don’t build houses like they used to”, implying that modern building standards and methods are poor, then they have never seen old houses stripped back Victorian and Georgian builders built terribly

Rubbish bricks

There is a 70mm gap between the outer and inner leaves of the rear wall where it meets 87 Culford Road! This requires a sudden re-think of the demolition process. Once the inner rear portal steel frame is in place, we strap the wall together using 150×50mm timbers inside and out, bolted together using threaded rods. We then work above our “clamps” and gradually move these timbers down, taking the broken-brick wall down VERY carefully. Also we fit stainless steel “helio-bars” across the cracks and sand cement render the party walls in an attempt to hold the building together. To make matters worse the middle wall rear wall has bowed outwards and the bow has been taken out with around 50mm of render. This means cutting the wall up with angel grinders, as attacking it with hammer drills is just too risky. Apparently the speculative builder was going bankrupt as he was building the De Beauvoir estate and hence he used up of all the dross and brick waste as his brick suppliers would not sell him any more materials. Another boom and bust building cycle!

March relief By the first week in March the demolition is finished, the steels are in position, and the rear portal frames are in place and “chem-fixed” to the party walls where possible. Quite whether the frames are holding the walls or the walls are holding the frames is a moot point. In fact there are no solid bricks to fasten the outer frame to, so we cast concrete to hold the steel and the wall together. When this is all done, I breathe a sigh of relief – it has been a worrying couple of weeks and the scariest demolition in my 30+ years of building.

18th March and finally we all change our jobs and become builders rather than demolition workers. From now on we will be carrying stuff into the house rather than bagging up rubble and carrying it out and dumping it in skips!

Client Robert Cohen

Not just like any other job At the “before the build starts” party everyone was saying to me when I was introduced as “Bron’s brother the builder”, that I must be very excited by this project — but I wasn’t; it was just another build. To me it was going to be just the same: hammering nails, driving screws, laying bricks and the endless moving of materials either out to a skip or back into the house, same as all jobs. And it is the same: bags get filled with rubble and dumped in skip after skip after skip, and materials have to be carried back in to the job (but at my age that is why you employ younger workers). As the job proceeds, however, there are new problems that are thrown up. These range from the simple — 200mm cavity walls need bigger ties but Magmatech provided them; to the more complicated — how do we avoid the implied cold bridge if we build as one would normally; to the still-to-be-solved –do we have to worry about water coming in through the 9” brick front wall, can we put the insulation against the brickwork without any ventilation? I think you can; Bob the Architect thinks we need 25mm vent space. I say that the rear cavity wall has only 4” of brick and there is no ventilation there; Bob says that English Heritage say there is a problem; I say that if you put a ventilation gap you then have moving air and Newton’s Law of Cooling specifically says that the rate of cooling of a body is directly proportional to the difference in temperature if the body is in a draught (I knew I paid attention to those physics lessons for a reason). The biggest reason I can see for NOT putting a ventilation gap is that we are going to great lengths to make the house air tight and then we introduce four air bricks – we might as well put in a cat flap and letter box whilst we are at it! The reality is that neither of us knows and we are making guesses based on hypothetical conjecture! The answer will come from Knauf, who are providing the insulation, when Phil Rigby their insulation expert visits the site.

All this, and at some stage I have to tell my sister that I am off to Turkey to run an International rafting competition for two weeks in June!

To hear client Robert Cohen discuss the challenge of this refurbishment go to the existing housing webinar run by Building magazine in May 2009

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