I recently read that the "industry standard" for how long a timber frame building should last in England is 200 years. What is your standard?

Since we live in an age of disposable products, planned obsolescence, and where typical household utilities are rarely designed to last more than twenty years, how long do you intend your buildings to last and how far do you go to achive durability?

Jim

Jim, my hope is to have my buildings last longer than the majority of newly constructed buildings. Not only longer but I am using screws which I believe will facilitate deconstruction. I will either be cursed or praised, I am leaving a package of bits with the structures with an assortment of bits, as keys, to the dismantling of them. If the workers of the future will be fortunate enough to find the packet they will surely appreciate them. This is my part, being added to the durability of the structure.

I would be rather pleased to have a build or two go 200 years. There are many factors that come into play which could effect the life of a building. My first goal is to please the first holder of the building. I have already seen one of my building change hands and uses. I went into it and looked around, a section of wall had been removed to facilitate an opening, I looked up into the open 2"x2" mortices left vacant by the removal of 3 or 4 studs.

And I am trying to limit the use of paint, even they new paints.

Tim

For true sustainability, the timber frame should last at least as long as the age of the trees used in the structure.

The design life of modern concrete, according to Prof. Mehta, is but 50 years, so that is likely one potential limiting factor if the foundation in our new structures is to be conventional Portland-cement based concrete.

The old buildings around here in New England that have stood for 150~200 years are sitting on stone, and one can readily observe instances where the foundation detailing was not thorough enough as the outset.... Lots of lessons out there to be taken in. Cap and boots must be sound. You can't count on future owners of the structure to do maintenance or have the financial resources for keeping the structure in good shape. You can, at best, only control what you design and build (and I'm not saying you can control that 100% either).

Buildings 'learn' after they are built as Stuart Brand puts it, and designing a structure with an eye to flexible future modification is a wise course I think. Mechanical systems need to be easily accessible for service, amendment, replacement.

Something tells me that oil or gas based heating systems will be going the way of the dodo in the next 30 years. Not quite sure if drill baby drill is going to solve the big picture supply/demand problem, if you know what I mean.

The downstream usability of building components is also something to take into consideration - what in this wonder structure will lend itself to future re-use/adaptation/recycling, and what will go straight to the landfill?

Timbers fatter than, oh, 4"x4" are likely to be highly recyclable years from today, however if they are laden with nails or other fasteners, or simply have loads of closely spaced notches, mortises, and so forth, the re-usability does decline. If years from now the timbers have twisted and checked badly, had sapwood which is now bug-eaten, well, re-cycling becomes less desirable an option. It already costs too much to pay the labor today to de-nail on old stud as opposed to working with a new one, though of course labor costs may well trend downward in the future making this a more reasonable proposition.

SIPS? I see landfill. Sheetrock? I see landfill. 2X studded infill walls? Landfill.

I don't see any reason why a timber building couldn't be designed and built to last 250 years. The details are what get it there, and a bunch of luck too!

Chris, I have 4 out of 7 buildings sitting on stone at my home. Well, really two of the four are, the other two are sitting on sip window cut outs and wanting stone.

So, creating a building which carries a " spirituality" can and will attribute to its life. I am subscribing to the belief in geometric design as part of that spirituality. The proportions attached to a building will have a lasting effect, for the building will bring with it an appeal. In effect it will vibrate a positive effect, keeping it alive.

Certain woods, granite, limestone, and clay all have a built in quality to them, adding to their longevity. It is not just that they are durable, there is something in their make up equalling a positive. PVC does not contain this positive aspect.

Tim

that's something to think about.

the lives of our buildings are wrapped up with our own lives.

big overhang and good foundations up off of the ground. replaceable foundations and a replaceable roof could help. i heard that the swiss flip wooden shingles over and smoke them to preserve. is this true?

an interesting theory- albert speer proposed a 'theory of ruins'- that the way to longevity in design was to build in such a way as to intend decay, building inspiring ruins. this is a romantic idea to entertain. what will your building look like in ruins? will that clearing in the woods, the chimney, the fallen arches, still inspire hospitality and make our remnants feel as if the world is their home? i heard another story about finding a wood canvas canoe, rotted in the woods, where the brass tacks had fallen in the perfect pattern of a set of ribs. maybe i made up that memory. still, interesting to consider the limits and possibilities of what human beings can make.

I guess I'm torn on this... To have the ego to build something that will outlive me and be around - a legacy or blight - or to come to a place to build in the way nature might - when I walk away, and not maintain - it eventually returns to the earth...

But its a big question...

Hmm, I don't resonate on the piece about ego being involved in constructing things to last. If that is a worry, then the answer is a simple one: leave your name off it, be the unknown craftsman. The vast majority of old structures we inhabit were built by people who remain anonymous, and that doesn't take away from what they accomplished by one iota.


How about, instead of ego, being motivated by the inspiration and standards set in the work done generations past (or the odd example of that to be found today)? How about being motivated by the desire to leave something behind that future generations might thank us for? How about being motivated to do the best work you can, not out of fear of failure, but out of honoring the materials you work with, and being willing to risk? There's lots to draw from besides ego it seems to me.

And if what is built IS judged to be a 'blight' after all the work to build it, not a 'legacy', then you can be sure that others will do something about it eventually. If it's worth keeping it will probably be kept. Of course, one person's blight is another persons delight.

And if the idea is to build things that return gently to earth, then the answer in any case is low embedded energy in materials chosen and ease of recyclability/reusability when the time comes. Use materials that don't have to travel far to site. the short list is earth (clay,sand, etc.), stone, and timber. Materials that can be easily worked upon, added to, modified.

An awful lot of people out there find a lot of personal/spiritual warmth and resonance to live in an old building, no matter how imperfect it might be. People love patina, history, evidence of someone taking care in what they did...and I'm thankful for that.

It is a big question and I am not an expert on the durability of various materials. I was curious if anyone would say they were using epoxy coated re-bar in there concrete foundations, installing termite barriers in locations that do not yet have termites, using rain screen walls, or designing for global warming.

Well fitted, dry laid stone has proven to be worthy of thousands of years of service.

Chris, I liked your comment that "For true sustainability, the timber frame should last at least as long as the age of the trees used in the structure".

Tim, I didn't know you were building with screws. Adaptability and repairability are surely important factors.

Historically, wooden buildings were seen as second rate compared with buildings of stone walls and tile roofs.

There is a lot that can go wrong. Fire, wind, insects, water, urban renewal, fungus, war.

I am not thinking clearly and I need to go to bed. More on this some other time.

Jim

i think there's a good bit of sense in dry stone foundations.

that said, even with a really solid foundation, a wooden building is as alive as the trees it came from, and remains so always. the point is not to freeze it in time, like a ziplock bag building, but to allow time to run off of it with some grace. all things are by the grace of god, man and nature. even the moisture from our breath does something to degrade the walls we live in. can a building be repaired? is there another tile nearby that can be added to the roof after a storm? my first experience with building was crawling under my dad's first log home- really an astoundingly wild structure- one stone wall, floating hudson bay corner walls, and a pit dug for a furnace in the middle of a boil of moving clay. we have kept that cabin standing through my life at least of seasonal work with a small jack and turnbuckles. every spring, when the clay thaws, the longevity of that building is called into question, and the smallest one squeezes underneath to try to keep it standing. if you want the future to thank you, build your crawl spaces bigger.

Hi Guys,

This week saw me inside a most peculiar building probably dating from the early 1300's. It was fully equipped with decorative saltire braces, clasped purlins and a 5 sided ridge piece - the first time that I have seen this combination. Methinks that it was a very early experiment in the transition from crown post roof to queen post / purlin roof. The most remarkable thing about this house was that the principal members of the frame were almost intact and where missing or changed it was still possible to decipher the pedigree of the frame - not bad for nearly 700 years.

I stood in an upper story (now bed) room and cannot remember the last time when I felt at such ease and peace with myself. This was not a large McMansion building but a simple 3 bay frame 14.5ft wide, 12 ft to the wall plates with 3 equal 10' 7" bays, with the fair facing all in one direction except the last frame.

Changes do happen over the centuries - a 14th century person's building dream is now another person's dreaming place.

Regards

Ken Hume

Hi,

Here is a digi pic of the Saltire braced building.










































Regards

Ken Hume

That's a very tidy and sound-looking building. It's been blessed over the years to have have caring owners with the means to maintain it. I note the mudsill is a good 18" (in my est.) off the ground, on a stone wall. The gable end wall looks to have a long stone sill. I'm surprised there is no post on the first floor between the two windows. What part of England is it in?

Hi Chris,

You are spot on with your original design suspicions.

The left hand sills have been replaced and raised as original sills and post bottoms have rotted off. Check out the difference in elevation of the post bottoms between the left and right hand posts.

There is a middle post in the ground floor (what you call 1st floor) but this is now concealed on the exterior by plaster.

This building is located in Olde Berkshire (now Oxfordshire).

Regards

Ken Hume

So what are the biggest enemies to longevity. I think, Gravity and water. You can't defy Gravity, it helps them stand and fall. Water, yikes.

Ken, was there any evidence of rising damp in the house pictured?

Hi Mo,

Probably the biggest enemy faced by old buildings is an excess of money ! This promotes the desire to make dramatic and sometimes quite inapproriate changes.

The external sills on the building above had rotted off all the way round and had been replaced by cutting the posts shorter and inserting new sills at a higher position but the internal sills were original and these were set on a dwarf stone wall. The area where the house stands was known to flood. In front of the house is an elevated roadway called a causeway which acted a bit like a dam and also provided people with a route that could be walked during winter. The house today appears to be quite dry inside and there was no smell of damp.

Regards

Ken Humne