Anyone in the building and construction industries, depending on their scale, often advertise in local magazines, yellow pages and sometimes door to door flyering for their business marketing.
This way of doing things has paid off in the past and can also be enhanced by having a website to refer people on to once they have seen the ad or flyer.
A few photos showing some portfolio work, such as different aspects of building construction, projects and detailed jobs would give the viewer some trust in previous work. These images could also include trade vans, premises and team shots.It would be a good idea to have certification images from accredited bodies and anything else that shows the building company to be contractable.
A contact form could send an enquiry to a specific email address that could be dealt with by office staff for a larger organisation or go to an inbox on a smart phone, so that the builder can respond whilst away from the office.
Keeping track of old customers and reminding them of your presence with offers of health-checks, follow ups or discounts on parts are all suggestions that would work really well with a electrician promotional strategy.
A construction company or builder is often limited to a particular area due to traveling time & fuel expense. Unless it is a national or regional company that has different branches. This preferred radius would be a local search and could be matched to what people are searching for online.