__Building Costs Per Square Foot in the State of Alabama, USA__

The building costs per square foot in the state of Alabama (USA) depend on many things. Before we talk about the cost of materials and labour, which is what many people are concerned about, the overall cost of building a residential property also includes costs related to the design and planning phase as well as the pre-tender stage. You have to pay architectural design fees if you need a custom house plan. Geotechnical engineers have to assess the ground conditions on the site where your project will be located. They will undertake soil tests, determine the depth of firm ground and water level, which will determine the depth of foundations required for the building. Civil engineers have to find the location of underground service pipes such as water and waste drainage pipes. The weather and climate in your region will influence the design, as well as the ground conditions and terrain. In this post, we will look at the cost of building class 3 [Best Standard] properties. We shall look at the building cost per square foot for single family homes, multi-family residences (apartments with 2 or 3 units), manufactured housing, motels with not more than 9 units, 4-corner conventional recreational dwellings and 4-corner A-Frame cabins.

__List of 15 Cities in Alabama – Percentage Deviation of the City/Town Building Cost from the National Average ($X), in Descending Order:__

In the state of Alabama, there are 15 cities and the construction cost per square foot in each city varies from the state and national average by a certain percentage based on the location factor. The building costs shown below are based on the local construction index i.e. the cost of materials and labour. They don’t include the cost of land, loose furniture and variation in ground conditions or terrain. Ground conditions are assumed to be normal. The building cost percentage deviation from the National Average for each city is represented by the formulas below.

If $X is the *Average National Building Cost* in the USA, then it will cost the following to build a residential property in each city:

**Alabama -4% (4% less than X)**

- Bellamy 5% (5% more than X)
- Birmingham 2% (2% more than X)
- Sheffield 0% (=X)
- Huntsville -1% (1% less than X)
- Mobile -2% (2% less than X)
- Montgomery -2% (2% less than X)
- Auburn -4% (4% less than X)
- Scottsboro -4% (4% less than X)
- Tuscaloosa -4% (4% less than X)
- Selma -5% (5% less than X)
- Dothan -7% (7% less than X)
- Anniston -8% (8% less than X)
- Jasper -8% (8% less than X)
- Gadsden -9% (9% less than X)
- Evergreen -10% (10% less than X)

The City Cost List above and Bar Graphs indicate that Bellamy is the most expensive city to build in the state of Alabama, costing 5% more than the National Average Cost. The second most expensive city to build a residential property in Alabama is Birmingham, at 2% more than the National Average. It will take the same amount as the National Average to undertake a building project in the city of Sheffield, Scottsboro and

If anything below the National Average is cheap, then there are 12 cities in the state of Alabama which quite affordable building costs. Evergreen is the cheapest city to build in the state followed by Gadsden, at 10% and 9% below the National Average respectively. The cities of Anniston and Jasper will save you 8% in building costs. In the city of Selma, your construction project cost will be 5% lower. You will save 4% in construction costs in the cities of Auburn, Scottsboro and Tuscaloosa. Huntsville, Mobile and Montgomery are closer to the National Average at 1% and 2% cheaper than the National Average respectively.

Building in the overall state of Alabama is 4% cheaper than the National Average. The building rates in the cities of Auburn, Scottsboro and Tuscaloosa are equivalent to the Alabama State Average.

__Variation of Building Costs with the Gross Floor Area__

The cost of building a residential property in Alabama also depends on its total floor area. Generally, the correlation between the square footage cost and the floor area of a residential dwelling is a descending curveline. This is due to the fact that builders try to get as much profit as possible from small building projects. Intrinsically, big building projects have a high profit margin although the percentage for mark-up in the Bills of Quantities is smaller.

The trendline charts below show the relationship between the building cost per square foot and the property floor area in the state of Alabama. Charts are shown for Best Standard single family homes, multi-family residences (apartments with 2 or 3 units), manufactured housing, motels with not more than 9 units, 4-corner conventional recreational dwellings and 4-corner A-Frame cabins.

As you can see below, the charts depict a descending curve whereby the construction cost rate is declining with an increase in total floor area.

__Best Standard Class 3 – Single Family Homes (4 Corners)__

Min $130.08 per sf – 700 square foot dwelling

Average $152.30 per sf – 2400 square foot dwelling

Max $197.58 per sf – 5000 square foot dwelling

__Best Standard Class 3 – Multi-Family Homes (Apartments with 2 or 3 Units)__

Min $149.94 per sf – 400 square foot dwelling

Average $164.24 per sf – 1136.36 square foot dwelling

Max $196.25 per sf – 2200 square foot dwelling

__Best Standard Class 3 – Manufactured Housing__

Min $99.18 per sf – 500 square foot dwelling

Average $127.17 per sf – 1610.53 square foot dwelling

Max $178.20 per sf – 2500 square foot dwelling

__Best Standard Class 3 – Motels with not more than 9 Units__

Min $136.56 per sf – 200 square foot dwelling

Average $179.71 per sf – 952.94 square foot dwelling

Max $271.60 per sf – 720 square foot dwelling

__Best Standard Class 3: 4-corner Conventional Recreational Dwellings__

Min $136.46 per sf – 400 square foot dwelling

Average $174.66 per sf – 1577.27 square foot dwelling

Max $271.60 per sf – 3200 square foot dwelling

__Best Standard Class 3: 4-corner A-Frame Cabins__

Min $112.97 per sf – 400 square foot dwelling

Average $144.31 per sf – 1577.27 square foot dwelling

Max $222.04 per sf – 3200 square foot dwelling

__Equation of Trendline – Floor Area vs Building Cost Per Square Foot__

We can find the equation of a trendline for the six types of residential properties named previously. The trendline equation is applicable to each particular property under the Best Standard class 3, and cannot be used to calculate the square footage cost of another type of property. The equations for each property are 5^{th} order polynomial equations, and they are also represented as gradient/slope equations.

__Polynomial Trendline Equations for Six Types of Best Standard Dwellings:__

__Trendline Equation for Best Standard Single Family Homes__

y = 0.0003x^{4} – 0.0227x^{3} + 0.5892x^{2} – 8.9431x + 205.09

__Trendline Equation for Best Standard Multi-Family Homes (Apartments with 2 or 3 Units)__

y = -0.0001x^{5} + 0.0065x^{4} – 0.1504x^{3} + 1.6926x^{2} – 11.502x + 205.73

__Trendline Equation for Best Standard Manufactured Housing__

y = 0.0006x^{2} – 1.4054x + 114.57 (Polynomial order 2)

__Trendline Equation for Best Standard Motels with not more than 9 Units__

y = 0.0001x^{5} + 0.0018x^{4} – 0.1218x^{3} + 1.4x^{2} – 9.816x + 186.76

__Trendline Equation for Best Standard 4-corner Conventional Recreational Dwellings__

y = -0.0001x^{5} + 0.0088x^{4} – 0.2783x^{3} + 4.3211x^{2} – 36.465x + 302.94

__Trendline Equation for Best Standard 4-corner A-Frame Cabins__

y = -0.0001x^{5} + 0.0096x^{4} – 0.2704x^{3} + 3.78x^{2} – 29.738x + 247.57

__Trendline Gradient/Slope Equations for Above-Named Six Types of Best Standard Dwellings:__

y = -2.4098x + 184.83

y = -1.9582x + 186.76

y = -1.3976x + 114.55

y = -4.0261x + 179.93

y = -5.1346x + 233.71

y = -4.2343x + 193.01

From the equations, Y is the building cost per square foot and X is the gross floor area of the property (GFA). To find the square footage cost (Y) of a particular dwelling, substitute X with values of the gross floor area.

__PDF Downloads__

__Useful Resources and References:__

Craftsman National Building Cost Manual USA