What it Cost to Build a House - plus notes on working with the inspector.

"What does it cost to build....?" The most often asked question on this website. 

Use this short article to estimate your building costs. Building and materials cost vary depending on what you put in to the house and the simplicity of your design. While this will vary by location and personal choices, the most obvious determinate of cost is the size of the building. So, we will estimate construction based on the total square footage of the structure. Use the outside dimensions to determine the size and add all the usable floor area that will be finished for living space.

Construction Cost Notes

We built our simple owner-built flat roofed cabin for $10/sf using new materials except for the windows and doors we already had. That was several years ago so this would definitely be at the lower end today. This is for an insulated rustic cabin without wiring or plumbing but with a simple wood interior. The gable roof cabins with a loft would cost somewhat more. A good estimate for such a structure might be $15-20/sf for materials assuming you buy carefully. Check the Gallery of houses where owners have shown pictures of their projects. Many have information on their costs. For an inexpensive house see: This one and This one.

The upgraded 14x24 Builders Cottage, Victoria's Cottage, the Grandfather and all the 20' wide houses all have upgraded foundation options, 2x6 walls and better insulation and windows. They also have full plumbing and wiring, of course. These buildings can be expected to run about $35-45/sf for all new materials. The average cost for cabin and cottage construction, contractor built, is about $70 to $95 per square foot (house only). So an owner-builder can save almost 1/2 if they have the time and experience. Note that there are also wide regional variations, especially in labor costs.

Our members often report back on their costs in the Owner-builder forum. Also... the Google links at the top of this page often update to books and links that are helpful in cost estimating. Use the little blue arrows to toggle through the list.

Here is our Quick Cost Estimator for pricing an initial floorplan and any options the project might involve. To use this you need to have an idea of your base line living area cost per SF. You can ask building officials, builders or building supply houses to get an idea of what conventional construction is costing per SF in your location. This will be a standard contractor built price for a house about the size you are planning to build.

If you know you are going to be doing some part of the construction you can reduce this figure 10% to 50% based on your expected involvement. (Contracted costs are about 1/2 materials and 1/2 labor.)

Use your projected living area cost and multiply it by the main living areas (add all floors) that will be insulated and heated. Then, calculate the area of any additional items below and estimate them by using the factors as a multiplier of your main SF cost. Adding these all together will give you an initial construction cost estimate.

For example: If your partially owner-built living area cost estimate is $70/sf, then your roughed in basement will cost (70 x .4) = $28/SF

In addition to the house construction there are site infrastructure costs that are somewhat independent of house size — water hookup or well, driveway, septic system, power connections, etc.

Estimating Materials

Some of our houses now have an optional materials list and some do not. If one is not yet available for the plan you want, consider taking your plans to a local lumber yard as they may be able to do a free takeoff and cost estimate of your project with the expectation you will order materials from their yard. If you will be working with builders, you don't really need a materials list, as most do their own takeoffs for each stage of the project.

Building Permit Notes

All our plans supply you with all the blueprint drawings and details normally needed for building permits. You may copy any CountryPlans plan set locally to have additional sets for your own (single house) project - you do not need to order multiple sets. On some of our plans you will want to add in some of the included options to customize your plan set before submittal.

Our drawings meet or exceed the general requirements of national building codes. They may or may not meet all your local requirements. Some locations have specific special requirements such as high snow loads, wind loads, and earthquake loads. Some jurisdictions will require that ALL plans are stamped by an engineer registered in that state. Some building departments will not allow all the foundation options we include in our plans.

In short, you may need to modify your plans to satisfy local conditions or opinions. This is true of any stock plan you would buy and even custom home designs you have done by a local architect. Contact a local home designer, engineer or architect if you have required structural modifications. Smaller items such as extra hold-downs can often just be added as written notes on the plans right there at the permit counter. This is what most builders do - just draw on the two sets that are submitted at the permit desk.

Any stock plan, modified plan, or owner-designed plan should be reviewed by a local building professional to make sure it meets local codes and climate requirements. This is standard boilerplate you will find on any plans. We go a step further and include information in your plans packet on how to work with the building department and such tricks as a "presubmittal" review to see if you need to make changes. (This can save a lot of time.)

Finally, you can expect any approved plans to come back marked up with some additional notes added. Many of these are things you or the subcontractor would do anyway.

The building permit process and can seem frustrating at times, but is actually helpful to you as an owner and is done primarily for your own safety and the longevity of the building. A good building inspector can help you do a better job of building your house  — so try to see them as a construction resource (which you have already paid for in the permit fee!)