It’s not difficult estimating costs for small houses. Simply add up the number of each main component and multiply times a realistic cost. Then add about 5%-10% extra to cover unforeseen expenses. Use current, local prices for most accurate results.
Here’s one article that explains how to estimate the number of bags you’ll need.
You can also do a per square foot cost estimate. This method is not as accurate as a detailed cost breakdown, but does provide a rough estimate.
Here’s one example using dirt cheap building techniques. $10/sq. foot is about as low as you can get using simple, low cost materials and methods (earthbags, rubble trench, earth plaster, locally harvested wood, recycled materials, etc.). So a house of about 300 square feet would cost around $3,000 not including land or labor. (300 x $10 = $3,000) Then add any extras you may want: radiant heat, better windows, tile counters, etc. to get a more accurate cost. The cost will be significantly higher if building in areas where you have to meet building codes. Seek out remote, rural areas with few or no building codes to minimize costs.
7 thoughts on “Estimating Costs”
I’ve spent many days reading the countless informative articles you have written. Firstly – Thanks, I’ve found them to be very interesting and worthwhile!
Secondly, your square foot cost estimate calculation.. I’m living in Cambodia and plan to build a roundhouse (quite possibly purchasing your PDF plans for this project) and dome over the coming months. Considering the lower costs associated with building here, I’m wondering if this would come down and if so, roughly by how much. I’m aware that you’ve worked in Thailand and have travelled through there myself. From my experience I expect to see at least a 20% reduction on anything not specialist. Labour costs are incredibly low – the average monthly salary for a Cambodian labourer is lower than $80.
Email me at strawhouses [at] yahoo.com and we can talk more about this.
Do you have any suggestions as to how we can seek out those remote, rural areas with no building codes? I’ve been having a really tough time with that.
Yes, there is an e-book that was just published that lists all of the states, county by county and reports what their status is regarding building codes. You can order this here: http://www.greenhomebuilding.com/building_codes.htm#books
Jacki, some states are more lenient as far as codes: states out west, Texas, Missouri, Kentucky, and some others. Once you decide on a particular area, do a lot of Google searches. Be sure and search for “ecovillages” since many of them build with alternative materials. And at some point it’s best to spend a lot of time in an area searching for the best deals.
Is there a way to bring down costs if you build many houses in a lot? For instance, in Haiti, if you have an acre or hectare of land, how many houses with room for the house to grow, a yard and a garden could you fit on there? What percent in savings can you get if you build how many houses together? I assume that you can make fewer trips for getting soil, sand, etc. If day labor is the main cost maybe you cannot save much on that.
Denser housing is typically more affordable since cost of land is often a major factor. But it’s difficult to say how many structures will fit on a given amount of land. This is probably something best decided by local communities. We all want X but have to settle for Y. Same with deciding on house sizes, etc.
Building adjoining structures with common walls will greatly reduce costs and labor. But then you have to figure out how to provide adequate ventilation, egress, outdoor living space, etc.