In our business we visit many, many properties throughout Austin that we are asked to consider the pros and cons of renovation versus demolition and new construction. Here are some factors to consider:
1. Is the existing house in a Registered Historic District? If so, you may not be allowed to remove or demolish the existing house.
2. Will you attempt to live in the home through a renovation? You might want to seriously consider moving temporarily. The expense can far outweigh the stress of living in a construction site. Just to remind you, here's what a renovation can look like:
3. Is the existing house layout useful or is it inefficient and unsuitable to your lifestyle? With a new house plan an architect can tailor the design to your exact needs without wasteful spaces.
4. Are there concerns about the foundation, plumbing or electrical? If any one of those items need replacing your renovation could get expensive.
In central Austin where we do most of our work, the typical old house is as follows: 1,200 sf, pier and beam construction (with the piers often being 80 year old cedar tree stumps), wood siding, un-insulated walls and single pane wood windows. We don't want to be proponents of tearing down relics of the past, however if we're talking about pure construction costs we have come up with the following formula that proves well over the years. If you are adding more than 50% to the existing size of the house it will be cheaper to remove the home and start over.
So, for that typical 1,200 sf house you may want to add a 500 sf bedroom suite. If the rest of the house can be kept relatively in tact a 500 sf addition could prove economically viable. On the other hand, most people want to not only add 1,000 sf (and bring the house up to a more useful 2,200 sf) but they will plan a complete kitchen remodel, window replacement, adding insulation, new electrical, shoring up the faulty foundation and fixing leaks and termite damage. Once all of this is consider it becomes much more cost effective to build new. And even with today's prices, $200/sf can still buy you a very nice house. Plus, it's much easier to predict construction costs on new construction than renovation/addition work.
As Austin architects, it's our responsibility to know the city's restrictions - the zoning code, the McMansion Ordinance, the Historical code - but we also need to be aware of relative construction costs to properly advise our clients before the design process begins.