I'm not saying it should or should not have a blog... All I'm say is if you had a blog and you created an article (let's say a case study on a recent kitchen you fitted) - that article is going to contain keywords that will show up in search engines for longtail keywords. Then people might link to you about a tip you gave or an article, and you gain a back link.
Courtesy of Google
Quote:
| Frequency distributions for online searches show large numbers of less popular, niche keyphrases being used to search for products and services ... |