June 2016 Update and Self-Build Live

June 2016 Update and Self-Build Live

I find attending exhibitions a great chance to talk directly with various suppliers and to see examples of their products. While continuing the voyage of getting pre planning lined up I headed over to Bicester, UK for the day to see what the show there was like. I'd attended the Ideal home Exhibition and the Self-Build exhibition but was curious what differences I would find.

The best two contacts I made were with 'Trish in MBC timberframe and Andy from Sunamp. Besides this there were several other stands that took my interest and the talks in the afternoon when I wanted to rest my feet proved interesting..!!

MBC Timberframe

I'd heard great things about this company. They currently manufacture in Cahir, Ireland but most of their market is in the UK. Patricia was kind enough to sit down with me and answer loads of questions I had about the whole process. She is an Architectural Technician and is a PassiveHouse Designer so knows all the ins and out plus bags of experience from all the projects MBC have undertaken, what to watch out for etc which she freely shared.

The payment system was one of the first things I asked about. With an arrears based mortgage would I be able to afford to order a timber framed house? They have several stages and as each is reached they expect payment at that exact time, not 30 days hence. It's split out quite well with 6 stages so I hope the bank will play ball:

Deposit - 10%
Sign off Drawings - 15%
Delivery of Foundation - 20%
Delivery of Timber to Site - 20%
Completion of Timber erection - 20%
Completion of Air Tightness Test - 20% (using a third party which MBC pay for)

Now I know my maths is out but that gives you a rough idea, you'll need 25% to get the order booked and in their queue, that will take about 12-13 weeks currently. Once they get started you'd better have the next 60% ready as they work fast!! You should only use the information provided here as indicative, contact your timber framed provider for an official list of their pricing structure.

Some other tips/notes 'Trish provided were as follows:

• Get your roof tiler in before MBC finish up to check their finishing match up with what roofer requires to lay the tiles
• Cellecta screed board 28 is brilliant for first floor noise dampening. They usually use it in apartment builds but I read a lot about noisy 1st floor wooden floors and this product could be part of the solution. Rockwool and sound block plasterboard for rooms such as the bathroom would also be advisable! 
• They supply the twin stud without insulation and pump it - cellulose insulation (=warmcell) onsite so that it easily bridges the gaps between the panels. They use something like an apple corer to check the density of the insulation through a section of the wall afterwards
• Fill any WC's / sinks  with water and seal off any pipes / window handle holes (!) before doing the air pressure test - some failures are due to keyhole in window handles!
• Bi-Fold doors have air tightness problems - I was hoping to use them but there are only two I could find meeting Class 4 but this might not be enough
• They use Scandanavian Pine / Larch with C16/24 rating
• Cover the MHVR ducts until commissioning to prevent dust / plaster / bug contamination

Sunamp 

These are an interesting company I'd been aware of for a short while but I'd not spoken to them before. Their man Andy was very knowledgeable and I got a hot pocket which shows how their Phase Change Material stores and releases Thermal heat.

He suggested using a pair of batteries for Hot water and another for under floor heating. They can be recharged with night rate electricity and an Air Source Heat Pump. I was planning on PV but wintertime is when this will be challenging. I'm still thinking about using one of their units but want to see what my heating demand is first in the PHPP. Worth checking out though!

The main interest of mine is their ability to take in cold water and output it at 58 degrees or with a mixer, a lower temperature. I take 3 minute showers so if it's just me this could provide my daily hot water easily. I'm hoping to avoid a 300 litre hot water tank, it's just a waste for one or two people!

Rainwater harvesting

This was surprised me as they have a well thought out solution. My first question was stagnation. They have a system that automatically recycles the water in the header tank (100 litres) if it doesn't use more than 85 litres in 3 days. This just refreshes from the rainwater tank so you're not loosing anything or wasting mains water. There is a holiday button which refreshes from mains water so it doesn't go stagnant also. The header tank is the way to go I think, a direct system has less flexibility. Most of the tanks they sell are shallow dig tanks laid about 2 meters deep, they can hold 1500 - 7500 litres with various sizes. You just need to keep the water table over the top of the tank.

For prolonged power cuts there is a manual mode and they reckon the whole system costs 1p per person per day to operate. The header tank should be 1.2 meters above the highest toilet and 5 meters above the washing machine. Maintenance is simple, check the steel filter and wash out any silt with a £30 dirty water pump every few years. The pump in the tank is a sealed unit but very reliable. There is 330mm from the top of the tank to the ground so freezing should not be an issue.


There was a lot of other stands including a house they had built of ICF (without the concrete). ICF is like the lego block system of construction and interesting! I also spoke with an Enphase Rep about micro inverters and a new Lithium-Iron battery system they are releasing this year. It's IRON not Ion so has a much safer threshold necessary for domestic usage!

I also watched a presentation from Build-Zone who do structural warranties and the pictures of some of their scare stories! One house burnt down due to overloading a power extension during construction, imagine that when you're on a tea break and there's little left! Well worth checking you have sufficient reinstatement cover and read your policy documents! Get the structural warranty arranged before you start building as the inspections allow them to assess the risk, otherwise you'll pay a lot more as they have to cover themselves. Regarding theft, it usually happens within 3 days of delivery, usually someone on the build makes a call. Recording the arrival / departure of all workers helps mitigate this a bit as word will travel that their presence has been noted and blabbing about valuable materials that just arrived onsite will hopefully not happen.

Links:

http://www.mbctimberframe.co.uk
http://www.cellecta.co.uk/cellecta-brands/screedboard-acoustic-insulation-boards/screed-board-28-acoustic-floor-insulation/
http://sunamp.co.uk
http://www.rainwaterharvesting.co.uk
http://www.build-zone.com

In case you haven't heard or don't know ebuild forums are closing down and buildhub has been setup as it's spiritual successor:
http://forum.buildhub.org.uk/ipb/
This is a good place to ask advice!