Tree-ring dating

[MikeG]

Spurred by this thread, I had a good conversation with a dendro guy on Friday. To get a good date, they need a sample which includes bark (preferably), but at least sap wood, and all the way to the heart of the tree. They need about 60 rings to be getting accurate, but anything over 45 (in the heartwood) gives them a chance. Further, if you have three separate but all marginal samples they'll likely get a date which may be more reliable than one pretty good sample. The chap I spoke to charges £150 for up to 3 samples sent to him (loads more if he has to come and take a wood-core himself), and there is no fee payable if there is no dating achievable. The lead time is about 6 weeks, and the samples can be returned at your own cost. If there is bark, a clean sample, and 80 rings or more, they can be almost certain of giving a date to the exact year the tree was felled.

 

[Pennyviz]

Thanks Mike, that's really useful info.

 

[MatthewC]

The only place that I have seen old buildings that genuinely had timber from ships was in Rotherhithe in London - given that the local industry was ship-building and breaking, it rather makes sense. The rather beautiful local church has furnishings made from timber from the Fighting Temeraire.

I used to live near Surrey Docks and was churchwarden of a different church in nearby Bermondsey. You could still find (only ten years ago) small bits of wood along the Thames (parallel to Rotherhithe Street) , with large hand-made nails in pretty good condition.

At the church there was a 12ft ladder (effectively steep stairs) going up the tower; I reckoned that this ladder has come from an old ship as it was very high quality and had polished, shaped hand rails. We also had ancient roof timbers which had been used elsewhere, and pine doors with very close graining (and a lovely smell when I drilled). NB Surrey Docks (e.g Norway Dock) was also where imported pine arrived when it first became available.

 

[Penners]

I heartily agree with the views expressed above about ship's timbers. It's amazing how many timber-frame period property owners have mentioned to me that their house was built with ship's timbers! As FF observed above, if all of these were true, great fleets of ships would have been dismantled in order to provide the necessary woodwork!

I have heard it speculated that the idea of ship's timbers being used for housebuilding has sprung from the use of cruck timbers and curved windbraces in many old properties. Their curvature could be seen as vaguely shipshaped, so may perhaps have sown the seed of this old wives' tale.

I'm also among those who are very sceptical about the value of dendrochronology or even radiocarbon dating in dating a house. As others have observed, there is no guarantee that the beams used were originally cut specifically for that property - indeed as you go back through time the average wealth of the population reduces substantially, so it's very likely that many properties were built with at least some timbers that were recycled from earlier houses.

You may have more success in finding the age of the house by asking an architectural historian to date its features - windows, chimney(s), roof structure, types of carpenter's joint - used in its construction. It is surprising how quickly fashions and techniques changed over the centuries, and a house can often be dated to a relatively short span of time by an expert in such details of its structure. However, if you decide to try this, do be sure to find someone who is specifically an expert on your area. Designs and techniques varied considerably across the country.

 

[xanthe]

The cellar sounds interesting xanthe. Could you make a judgement based on structure? If the house is supported by the cellar walls the cellar is unlikely to be a later addition.

My personal view is that the cellar is the oldest part and the house built immediately on top. We have lost the original sole-plates in 3/4 walls, but the remaining one is built right on top of the blocks and I would be very impressed if they had been capable of propping up the house in order to put them in underneath. The other houses in the street have cellars but none of them are built of sandstone blocks. The only one in the area that apparently does is a C18th house that was built on top of the ruins of the old college and their cellar is part of the original building.

When I finish taking out the bricks in the fireplace and removing the damp-proof course there, I will be directly on top of the blocks so will have a poke about - the inglenook is built outside the original footprint of the house and the footprint of the cellar.

 

[xanthe]

The only place that I have seen old buildings that genuinely had timber from ships was in Rotherhithe in London - given that the local industry was ship-building and breaking, it rather makes sense. The rather beautiful local church has furnishings made from timber from the Fighting Temeraire.

I used to live near Surrey Docks and was churchwarden of a different church in nearby Bermondsey. You could still find (only ten years ago) small bits of wood along the Thames (parallel to Rotherhithe Street) , with large hand-made nails in pretty good condition.

At the church there was a 12ft ladder (effectively steep stairs) going up the tower; I reckoned that this ladder has come from an old ship as it was very high quality and had polished, shaped hand rails. We also had ancient roof timbers which had been used elsewhere, and pine doors with very close graining (and a lovely smell when I drilled). NB Surrey Docks (e.g Norway Dock) was also where imported pine arrived when it first became available.

We must have lived very near each other - I was near the Pumphouse Museum. One of the nicest and less well-known parts of London. Are you able to say which church it was in Bermondsey - I know the area pretty well.