Owner Builder Forum
Feb 25, 2013 2:04 pm
I am a builder with over 25 years experience and I am passionate about sustainable homes.
My son wants to design & build a new sustainable home as an owner builder so I am going to help him.(he has no idea!)
I am going to go through the complete process from selection of land , design, council approval and then build.
I am going to post all of my planning, cost planning (bill of quantities), spreadsheets, programs, cash flows and photos throughout the entire process if anyone is interested.
We are going to use as much recycled materials as possible and also incorporate strawbale and hemp (building type)
The design we aim to achieve will be maximum solar passive using CSIRO design tools. He also wants to be off grid.
Because the design won't comply entirely with BCA I will have to get it reviewed and certified by an engineer specialising in sustainable designs.
I am not entirely sure if this is the best place to keep all the updates? I do have a website and facebook page where I intend to keep all the developments.
The reason I am doing this is because i have seen so many owner builders come unstuck because the planning has been so poor. Apart from running out of money they also tend to get the sequence wrong. (Sometimes why they run out of money!)
If you are planning on owner building then download the free spreadsheets and cost calculators from my website. There are also some gantt charts and cash flow reports that you can look at.They are fairly simple but effective. You just need excel.I have a fairly detailed BOQ I have recently completed for a client. That will also give you a good guide of current cost. Good luck!
PS The 'recycled' house shown on the website was built for $170/m material cost. I did all the work myself.
Re: Owner Design & Build a green sustainable home2
Feb 26, 2013 7:50 am
Oops. Problem number 1 so soon after posting.
About 3 weeks ago the son had found a block of land 10 minutes from here and it was in his price range.
It is a steepish block near the centre of a small town. No sewer.
There is a house next door and on the other side a vacant block.
Access to the front off the main road is steep but there is rear lane access and fairly level.
He made an offer based on a favourable geotech report.
There was no deposit paid but we did have to get permission to enter the land to do some exploratory dig.
With all the rain recently the test holes were postponed.
Anyway as it turned out yesterday they were able to do it.
The deeper the auger went the softer it became. Class 'P' site !!
The engineer advised us that we would have to do piering like screw piles for the house as well as land stabilisation down the length of the block.
We would also have to put in a double tank septic system to reduce the flow velocity down the hill.
I roughly estimate about $80k to do these works before building can even start!
The son spoke to the real estate agent last night to tell him that the deal was off.
He is disappointed but not as disappointed as he could have been.
The only cost so far has been $300 for the geotech. It should have been more expensive but we said not to bother providing us with a report.
Anyway the hunt is on for another block. I will keep you posted.
Re: Owner Design & Build a green sustainable home3
Feb 26, 2013 3:05 pm
Sorry to hear the bad news greenify but a lucky escape really. I'm really interested by the cost calculators on your website. When I've got a spare hour or two I'll have a go at using them. The recycled house you built for $170/m - does that mean $170,000?
Re: Owner Design & Build a green sustainable home4
Feb 26, 2013 5:27 pm
Hi Liliana yes it was a lucky escape. I had an inkling about the land based on the house next door. It had a fair bit of movement in it.
Yes you will need to set aside probably more than a few hours to get the detailed costs for your build sorted out. It will be worth it.
I have been watching this forum for a few years and I have noticed most owner builders say that if they had their time again they would have better control of their finances. Don't even apply for a loan until you know how much things are going to cost.
If you have downloaded the spreadsheets and calculators then save them in a single file in your computer and just keep adding the information. You probably haven't noticed yet but all the spreadsheets are linked so once you add info it updates your main dashboard page. You will have all your information with relation to cost at your fingertips.
I have been using this system for years and it works. I'm no brain surgeon so I need things like this to help me.
Good luck with your project.
Re: Owner Design & Build a green sustainable home5
Feb 28, 2013 12:47 am
Very interested in your project mate! Please keep the updates flowing!
I am currently trying to design for my owner build, a 2 bedroom 1 Bath super insulated dwelling in a small rural town on a <500m2 floodprone (1m) block. I really like the issacson davis beach house - http://oak.arch.utas.edu.au/publications/PDF/17s.pdf and am basing my design on it at this time. All for a small budget hopefully around your 170/m2.
Any available design principles you would like to share would be appreciated!
Re: Owner Design & Build a green sustainable home6
Feb 28, 2013 4:30 pm
You biggest problem is potentially the flood prone area. Last weekend we had our property flooded at a level never seen before by locals. Fortunately only fence damage.
If i were you i would consider getting your place as high as possible. The engineers will probably want as few obstructions as possible to stop flood debris racking. You probably end up on tall piers.
It looks like your design will be light weight construction so try and find and use as much demolition timber as possible. It is already seasoned and straight. You could even use tallowood floor boards for your external facade. It has good external durability. It is amazing what a quick belt sand can do to a bit of old timber.
Start looking now. I spent the day at demo yards and found some trusses that will be very handy. Now i have got the size i can make the design fit.
Re: Owner Design & Build a green sustainable home7
Mar 01, 2013 1:07 am
Yep, the 1% flood height is around 800mm, and council requires 500mm above that as freeboard so I have a minimum floor level of 1.4m. Which is about 300mm above the PMF. The Design linked appeals as it lends itself to being raised as it is on piers to begin with, so that's handy.
Sounds like you were lucky with only fence damage!
Plan is to use as much recycled materials as possible, however at the moment, I'm trying to get a budget together, so I am getting market prices for materials and finishes, some auction prices and whatever other data I can find together so I can identify budgets for all items and identify 'buy it now it's a bargian' items as well as get a good idea of how much the whole thing will cost.
What is your approach to glazing? Do you use second hand double glazing? How do you get around the certificate requirements of councils? My talk with council did not she much light on this. I got a very rough quote of 10-12k for glazing and if I could I would love to reduce the cost by half or more.
Re: Owner Design & Build a green sustainable home8
Mar 04, 2013 1:59 pm
You will have issues with certificates for glazing and structural grade timbers. You will have an engineer involved in your project no doubt. Before you engage him talk to him about your glazing issue. He will tell you what wind category you are in and what minimum glass thickness you will need. You will also need to consult him on the structural framing timber grade. He can write a letter that states DTS (deemed to satisfy) for structural.
For glazing there are a lot more things to consider. I have never used recycled double glazed units but I have had lots of homes specified with double glazing. When we run the thermal simulation on the home before doing the working drawings we determine which windows would benefit from the double glazed or low e coatings. Some windows in a house need it and some don't. You can end up having different scenarios around the house for max efficiency and low cost. it is worth the expense to get the absa certificate up front. That way you will know. Most of the issues you will have with a poor performing house is because of the windows. An absa certificate will also get the council on side with your glazing options.
Timber frame is also a good insulator but does require more maintenance.
Re: Owner Design & Build a green sustainable home10
Mar 05, 2013 9:32 am
Hi treeseachanger, we have temporarily hit the skids so you will have to stay posted.
I am still hunting the demo yards at the moment getting as much recycled framing timber as possible. So far so good.
I need it to stop raining!!
Side issue: the block we almost bought developed a big crack over the weekend and looks like slipping onto the road. So therefore I can't be too negative about the rain otherwise i would probably own that heap of mud.
Re: Owner Design & Build a green sustainable home12
Mar 06, 2013 12:46 pm
try and find and use as much demolition timber as possible. It is already seasoned and straight.
Good luck with that Time verses money, one comes at the exspense of the other, good recycled timber is getting very tough (and exspensive) to find and it is not often 'straight' when you get it cheap. It can be straightened but that that's time. You need to have a very good reserve of cash and a good means of transport to get materials when you see them. Building with recyled/salvaged materials will not save you any money if you do not outlay a lot of time chasing it down and/or working with it, quite the reverse actually, it can cost double. Designing a house then trying to source recycled materials is a very tough road to take. Getting the materials then designing the house around those materials is the cheaper option by far but will not give you the design out comes. It is about the compromises.
Re: Owner Design & Build a green sustainable home13
Mar 06, 2013 6:17 pm
Hi Steve, you are obviously speaking from experience which is always a good thing. I do agree with you on the majority of your observations but I must say that I have some really good outcomes using recycled materials.
The key is to act fast when you see an opportunity. I was able to buy a large bundle of lining boards that was painted brown and looked terrible.
I offered $200 for the lot and took it that day. When I removed all the copper nails and flipped the boards over and planed one side it was like new.
It turned out to be silver ash and I sold the nails for scrap and got my money back.
The key to the exercise is to be on the lookout. You just never know where and when opportunities arise.
Good luck LArge and start looking now.
Re: Owner Design & Build a green sustainable home14
Mar 06, 2013 6:51 pm
yep there are some great outcomes with salvaged and recycled materials, our house is over 50% recycled/salvaged content but it comes at a high time cost and in some instances a high $ cost also to get what is required. We scored some amazing bargins but I really put in the time chasing them. Cash, a car trailer and an extra sense for building materials do go a long way
Re: Owner Design & Build a green sustainable home15
Mar 06, 2013 7:52 pm
I guess storage space and an area to refinish timber is also on the must have list... I am loving the discussion here and would love to hear more... Perhaps we should have a 'salvage and recycled materials' discussion thread?
Re: Owner Design & Build a green sustainable home19
Mar 09, 2013 6:10 am
Make sure the nails are facing toward a cavity where I can or just hammer them down flat into the face of the timber.
I have to be careful when cutting the timber not to hit them. Pull that nail out.
Re: Owner Design & Build a green sustainable home20
Mar 09, 2013 8:17 am
I like denailing timber - Pinch bar, rubber mallet, a good pair of gloves and some good tunes on the ipod, away I go for days at a time.
Sign in or Join to reply to this Topic
2 more posts
SaveH2OGreen/Sustainable/Passive Home Builders - SydneyGreen/Sustainable/Passive Home Builders - Sydney
You need to consider the Urban Heat Island Effect and also much stronger winds. The pressure gradient between the South Pole and Antarctica is…
JS87First Build - Metricon Home Solutions DesignFirst Build - Metricon Home Solutions Design
Also, find out the manufacturer of the windows and ask them directly about security screen installation. Sounds suspect not being able to add them after installation.
oklouiseFirst time home owner wanting to extendFirst time home owner wanting to extend
no point making plans unless you know what you can spend so start with the bank and a builder will be reluctant top quote without a rough plan and a designer will be…
ArdoBuilder for lockup only, owner takes over to complete home?Builder for lockup only, owner takes over to complete home?
I don't think it's unrealistic. Builders are not interested in missing out on margins gained by making other trades do the work. After lockup it's all cream.