Architect costs. Costs Per Square Foot. Nearly, you have to spend almost $1000 to $5000 per 1000 square feet of area. Or an architect might agree to design a 25x25-foot room addition for $5,000-$10,000, or a 3,000-square-foot custom home for $50,000-$75,000 or more, no matter what the final construction price is. For a very general estimate, it is easiest to think about the cost to build a house per square foot, or more usually, the cost per square metre. For smaller remodels, a cost per square foot may be given to start, with additional costs added in revisions as the process goes on. I am not so sure how common this is but I do think many architects use this system. Breaking it down like this, at the lower end of the spectrum, a new build house might cost as little as £1,400 per square metre. COST PER SQUARE FOOT. Generating costs per square foot is a pricing method often employed in small projects. On an average basis, this cost will range from $1.25 to $5 per square foot area. However, many experienced architects could also charge $10 per square foot, which is quite a significant amount. Well, such a fixed fee is typically small for small-scale projects. Like new builds, the cost per hour ranges from $150 - $400 , while the cost per square foot ranges from $2 - $10 , depending on how extensive the remodel is and the architect’s involvement. Some architects charge based on a set cost per square foot. Based on the expected difficulty of the job the cost per square foot could vary. the set a rate and based on the size of the job they get paid accordingly. When an architect needs to work out the design or choose the building materials before calculating the overall costs of a project, this pricing method is particularly useful.