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Challenges left to solve in house construction?

formbypc said:
What would make it unfit for purpose, if the basic building materials are still sound?
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So, for example, my previous property was a victorian terraced house. Built to a good standard for its time from stone and brick. As built there was a bathroom off the kitchen, and an outside toilet. It represented a very good improvement in living conditions for its time.

However, for modern use and lifestyles the lack of car parking space, the loss of an upstairs bedroom for conversion to a modern bathroom and the inability to bring the property up to a modern level of energy efficiency were problematic (eg no possibility to insulate cavity walls, limited loft insulation space with low eaves, very draughty by necessity to keep damp at bay (eg vent bricks, underfloor cavities, draughts from unsealed joist ends into cavity, etc)). Additionally, a single-leaf brick party wall means that noise insulation between neighbouring properties is not at an acceptable level.

The point is that the houses were great when built but are not up to modern needs like cars, privacy and energy efficiency and can not be made so.

Older properties than that often have very low ceilings and doorways that are too low for a significant part of the population now (as people have got taller).

Who's to say that our requirements now will be right in 50-100 years time?
 
+1 Andrew,the economies of modular build are only there (i) for certain use classes and (ii) when you have a large number to build /high repeat rate and even then, it only works owing to the potential to shorten the time from planning consent to sale - minimising the borrowing period and improving cashflow; it can be worth building at higher cost to achieve that, for some developments. There are other system build approaches of course, and these are likely more flexible.

Also agree with your comment Andrew that there is little left that we don't already know how to improve.

Oh, actually - one thing - how to bypass the stranglehold on the stagnant nature of mass UK housng development design that the mass-market builders seem to have. It's like 'why are Hallmark cards so nasty?# - do they make them like that, because that's what they sell, or because that's what sells? Volume housebuilders place profitabilty before all else, and are very conservative ( and thus frustrating and hard work, to work with.) It's no my area at all.

But there is no shortage of clever & interesting & considered thinking going into housing in the uk, esp with smaller and flexible developers, and where developable land is under pressure, expensive, or the market prices are higher than average. How to get some of it as a normal expectation into the larger developments and nation-wide is the trick.
 
A few years ago we had Scotland's Housing Expo in Inverness. Full details are at the link below, but it was a showcase for different types of house construction and very heavy on green solutions. One of the side effects of super insulation during construction was that the tradesmen had difficulty working inside as they started sweating as soon as they did anything physical, and there was no fresh air flow through the buildings. As might be expected, some designs worked better than others in practice.

http://www.zerocarbonhub.org/sites/default/files/(Lori) A&DS ZCH 2015 Sml_0.pdf
 
We watch most of the home improvement programmes, including the US ones, if on Freeview. Renovation Nation I liked a lot.

Discovered some very interesting things in the UK and surprised what was and wasn't good for planners. Broadly the same but vary around the country.

Flood resistant was covered in Grand Designs with the floating house on/next to the Thames. Concrete box floating in a concrete box.
Also covered by the Dutch in their floating homes.

One thing not covered well is a sealed house and fresh air.
Seems some don't. Others have heat reclamation, similar to air con.
 
mikemusic said:
We watch most of the home improvement programmes, including the US ones, if on Freeview. Renovation Nation I liked a lot.

Discovered some very interesting things in the UK and surprised what was and wasn't good for planners. Broadly the same but vary around the country.

Flood resistant was covered in Grand Designs with the floating house on/next to the Thames. Concrete box floating in a concrete box.
Also covered by the Dutch in their floating homes.

One thing not covered well is a sealed house and fresh air.
Seems some don't. Others have heat reclamation, similar to air con.
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Sealed house with fresh air is easy! I've done that on every house I've built - MVHR unit plus careful detailing to remove air leaks.
 
mikemusic said:
Flood resistant was covered in Grand Designs with the floating house on/next to the Thames. Concrete box floating in a concrete box.
Also covered by the Dutch in their floating homes.
Click to expand...
The floating house was at immense cost and only going to work on the banks of the Thames where land is hugely valuable and there is no sacrificial land available nearby. I'm thinking of much more modest affairs, such as constructing levees along which the houses and roads are built, with agricultural land to either side. It will still be more expensive than building in a field that has a gentle slope and is 20m elevation above a watercourse, but we've just about run out of those.
 
stevec67 said:
The floating house was at immense cost and only going to work on the banks of the Thames where land is hugely valuable and there is no sacrificial land available nearby. I'm thinking of much more modest affairs, such as constructing levees along which the houses and roads are built, with agricultural land to either side. It will still be more expensive than building in a field that has a gentle slope and is 20m elevation above a watercourse, but we've just about run out of those.
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Presumably levees make the problem worse overall by displacing water, plus move flooding around in unpredictable ways? Lots of trees and stilts?
 
I have always found new build to be wasteful with land.

Why if we live in a country where building land is expensive/restricted that when building new homes a basement and a loft, are not incorporated. I am aware basement cost may exceed use but with the loft you are only paying for additional stairs, larger truss rafters and conform to fire-proofing regs, Although both items are costly, they do not increase the plot size.

Bloss
 
spent the last 4 months scavenging the area for a place to buy . amazing some of the construction . some of the council houses built in the 70`s are quite good in this area [midlands] . lots of space .

then again saw one next to a river and in food plain ....noooooo.....!

many of the modern houses are like rabbit hutch`s but people still clamour for them
 
andrewhockley said:
Presumably levees make the problem worse overall by displacing water, plus move flooding around in unpredictable ways? Lots of trees and stilts?
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They may do if not well designed, it's certainly a risk that you'd have to manage. Trees and stilts would work but you need to get vehicles in and out. There isn't any one size fits all, but humans have been living with the realities of living in low lying areas since the first man climbed out of the trees and discovered that the local riverbank was a pleasant place to stay, with a ready supply of food and water. I just think that with the pressures on housing that we have, esp in the SE, most of which is low lying after all, we need to come up with some 21st century answers to effective land use. The alternative is to move jobs and populations north, and that option seems to be beyond every government that we have had for 50 years.
 
blossomchris said:
I have always found new build to be wasteful with land.

Why if we live in a country where building land is expensive/restricted that when building new homes a basement and a loft, are not incorporated. I am aware basement cost may exceed use but with the loft you are only paying for additional stairs, larger truss rafters and conform to fire-proofing regs, Although both items are costly, they do not increase the plot size.

Bloss
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I've added an extra floor in the roofspace on the ones I'm doing at the moment. Cost increase was surprisingly large, but probably still worth doing. Certainly cheaper to do it at time of construction than as a loft conversion.

I costed a basement on a site I didn't buy and it was shockingly expensive. Building land is relatively cheap where I am and house prices limit what you can do really.
 
andrewhockley said:
I've added an extra floor in the roofspace on the ones I'm doing at the moment. Cost increase was surprisingly large, but probably still worth doing.
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Why was it so much more? OK, you need 1.5x the height of the walls or you need to add dormers, and you need a proper load bearing floor so heavier joists, and maybe a staircase (or space for) but isn't that all? Just thinking, do you need a beefier footing for a 3 floor house than 2?
 
martin clark said:
+1 Andrew,the economies of modular build are only there (i) for certain use classes and (ii) when you have a large number to build /high repeat rate and even then, it only works owing to the potential to shorten the time from planning consent to sale - minimising the borrowing period and improving cashflow; it can be worth building at higher cost to achieve that, for some developments. There are other system build approaches of course, and these are likely more flexible.

Also agree with your comment Andrew that there is little left that we don't already know how to improve.

Oh, actually - one thing - how to bypass the stranglehold on the stagnant nature of mass UK housng development design that the mass-market builders seem to have. It's like 'why are Hallmark cards so nasty?# - do they make them like that, because that's what they sell, or because that's what sells? Volume housebuilders place profitabilty before all else, and are very conservative ( and thus frustrating and hard work, to work with.) It's no my area at all.

But there is no shortage of clever & interesting & considered thinking going into housing in the uk, esp with smaller and flexible developers, and where developable land is under pressure, expensive, or the market prices are higher than average. How to get some of it as a normal expectation into the larger developments and nation-wide is the trick.
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Martin and Andrew,

What about a means to store enough thermal energy available in the summer as heat so that it can be used in the winter to heat the building?

What about a Stirling Engine to provide individual house combined heat and power?

What about apartment blocks that are above passive house standard (as can be found in parts of Europe), which may be more a problem of public acceptance than problems with the climate in the UK.

Agree that there are few problems left to solve, just seemingly the difficulty of selling to the public in the UK.

Ian
 
Houses have been built on stilts in Asia for centuries. The design challenge is water and sewerage when there is flooding
 
Thoughts on some of the issues raised:

water and sewerage when there is flooding

***Yes. Gravity is hard to argue with.

a means to store enough thermal energy available in the summer as heat so that it can be used in the winter to heat the building

*** Yes. I've seen suggestions that high levels of insulation in the ground floor is a bad idea (depending on ground conditions), and that what you should actually do is let the summer heat dump itself into the ground below. Obviously wouldn't meet building regs as currently written?****

a Stirling Engine to provide individual house combined heat and power
***I know nothing about stirling engines, but given energy requirements of modern houses (essentially nil), you'd need to think of the house as simply providing a site for a stirling engine, and ask if that makes sense.****

apartment blocks that are above passive house standard
****Well yes. I would have thought this would be really easy, given they are large buildings with high volumes to surface area ratio.****
 
andrewhockley said:
apartment blocks that are above passive house standard
****Well yes. I would have thought this would be really easy, given they are large buildings with high volumes to surface area ratio.****
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In the tropics apartments are terrible compared to houses, some thoughts:

No wall shading so the outside walls get really hot and windows let in to much sunlight.
Limited through ventilation
Lower construction standards - single layer walls, single glazing

Traditional hose construction in the tropics shades walls and ventilates the roof space
 
Coupe of quick thoughts on the first two items:
Seasonal storage is one of those things chased for a long time, had some serious attention paid as long ago as the 80s (see e.g. Littler & Thomas on energy use in buildings), but it's hard; you are looking to store rather large amounts of energy within an effective range of only a few degrees centigrade - difficult. Phase change materials (Glauber's salt and the like) in wall board have been out there for a long time, but doesn't seem to work as well as it could on paper. Buried tanks of water (since its the densest convenient medium in terms of specific heat capacity short of liquid hydrogen) as a seasonal storage medium also problematic - Things Tend To Grow in there; and even if you look to use phase change materials in solution its expensive on the huge scale required.

If your floor plan perimeter : area ratio is small enough, you can meet current part L requirements and leave-out insulation over much of the floor area to take advantage of the 'heat bulb' below. I've done it, and it's economic but of limited effectiveness - air temps are lowest at floor level, and it doesn't help floors above.

Basically, high insulation and airtightness dominate the UK appraoch and now the challenge is climate control (preventing overheating!) through right ventilation control and mechanical heat recovery. the weakness that remains in this route is workmanship, but that's also down to detailing in a way that is easily self-checked and deliverable. The last building of mine tested (35,000 sq.ft, 3 storey , concrete frame and heavy masonry cavity walls for client tech requirements) achieved an air leakage rate just 1/3 that of the Passivehaus standard for the volume involved... it is not hard. (NB Passivehaus requirement measured in air-changes per hour does not equate directly to the way BRE standard measures buildings, but its easily converted either way)
 
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