A Little bit about me...

I'm a Structural Engineer, specialising in conservation, at Hurst Peirce + Malcolm in London. I don't wear tweeds, am not particularly "cultured" and I'm not that old, but I do care passionately about the conservation of old buildings. I am a Chartered Structural Engineer, a member of The SPAB (formerly on the founding committee of the reborn Berks, Bucks & Oxon Regional Group), a Friend of SAVE Britain's Heritage and have recently completed a PD Diploma in conservation at West Dean College, with a view to achieving CARE accreditation. I hope to give you regular updates on my trials and tribulations as well as some insight into projects I am involved with and things I believe in.

Be patient with me - I'm no writer and I'm normally up to my eyeballs at work........

All views expressed here are my own.

Hurst Peirce + Malcolm, Celtic House, 33 John's Mews, Holborn, London WC1N 2QL

07854 624692 - richardsalmon9@gmail.com

Sunday, 22 May 2011

Listed Buildings on a budget - Maintenance!

I am presenting this blog not because of what I had to do, but because of what I didn't.

This Grade II* listed almshouses building in NW Herts dates back, at least in part, to the 15th century and much of the original timber frame structure survives intact, despite many subsequent extensions and alterations.

Before work started. 

From the other side Early 1900's (?)

Almshouses depicted on the right hand side of the "village" sign.
Being owned and operated by the local church trust (and still in use for its original purpose), it is clear that a carefully budgeted and systematic programme of maintenance and repair down the centuries has avoided the need for extensive and expensive repair events usually brought about by long periods of negligence. As a result, hardly any structural repairs were needed from me.

This is not a perfect example by any means, but it seems the bulk of the problems it has suffered have been the result of either external environmental factors, or previous well-intentioned, but flawed, repair techniques (using inappropriate non-breathable materials). One example of these external factors resulted in the need to replace large sections of the original sole plate and stud feet along the front elevation (not part of our brief), undoubtedly due to the closeness of the building to a busy road and the tarmac pavement tight to the building face. (I believe the new sole plate is now protected by a sacrificial lime render skirt and a drainage channel).

The old adage "A nice hat and a good pair of boots" still applies to all buildings. In essence keep new moisture out of the building whilst letting internal moisture escape.

Regular clearing of gutters and downpipes and checking for splits in flashings and slipped slates/tiles etc, will ensure that water cannot get into the building from above.

Keeping ground levels around the building low and permeable (with drainage if necessary) will normally avoid damp issues at ground level.

When considering "improvements", make sure that breathable insulation, plaster and paints are used so as not to trap moisture within the building fabric.

Other tried and trusted maintenance tips: Paint windows and doors regularly. Stop vegitation from climbing on building faces (use trellising if you have to). Keep trickle vents and air bricks clear to maintain internal ventilation. (I could go on, but fuller checklists are available from other sources, particularly your local council's conservation department).

Regular maintenance will save an awful lot of money in the long run.

Please see annotated photos below showing a few things we did have to deal with.

This old purlin had broken its back (some time ago) where connected to a wind brace. We just fitted a new secondary timber purlin above the old, to provide a "splint".

A previous cement based face repair here has accelerated the decay of the timber behind. Luckily the decay had not gone too deep so we were able to effect a "piecing in" face repair in timber. 

This gable leans outward quite significantly, but timber frame structures are incredibly resiliant when compared to their masonry counterparts. No structural repairs needed here apart from the addition of a couple of wind brace timbers to abate racking in the rafters. The brick infill between gable frame members also turned out to be tied-in and stable.

From another angle. See the gable lean relative to the scaffolding.

This chimney has developed quite a bow. This is usually due to both external weathering/frost action and internal sulphate attack. We decided it was going to be ok for quite a long time so just did some repointing and asked for ongoing monitoring.

This previous timber cover plate had acted as a water trap, accelerating the decay of the timber beam behind. Again, luckily the decay was not too deep and we were able to bolt on a new face section.