Cornerstone Home Inspection xxxxx en-us The Number 1 Most Common Destroyer of Houses Something as innocent and inconspicuous as water can cause and has caused foundations and structures to crumble. What can we do to prevent moisture in the basement? I received a question about what can be done to help prevent and stop water from seeping into the basement. How long does an average home inspection take? Usually a home inspection takes about two and a half to three hours. It can depend on a few different factors, including: the square footage of the house, if there are any outbuildings that need to be inspected, or if there is a crawl space that needs to be inspected. Each of those are things could add to the length of time, but in most cases you should allow about two and a half to three hours for a home inspection.