How to get it right: The problem with being offline on site

18.01.2017
Blog Post
Picture of foundations - article on offline foundations

While a lack of internet connection on a website can be frustrating, having offline masonry on a building site is worse! The photo below shows newly constructed masonry that’s not central on the excavated trench.

Picture of an offset foundation on a building site

It’s a common problem, most often caused by poor setting out or collapsed trench sides resulting in the actual shape of the foundations not matching the dimensions of the external walls. But does it really matter?

Well, yes, it does, because the loads of the finished building are transferred down the external walls and into the foundation where they should be distributed evenly into the supporting ground. The foundation width should normally provide a minimum 150mm spread on either side of the masonry.

Uneven loading can result in settlement and the detrimental effects on the structure can be extremely costly to rectify. You can design an offset foundation where the masonry sits on one side of the foundation – usually on a tight boundary, but the foundation usually has steelwork and minimum thicknesses of concrete to compensate for the offset.

The masonry in this photo needed to be rebuilt. Fortunately the build wasn't too advanced but still incurred unnecessary costs and time that could have been avoided by careful setting out.

Comments

(No subject)

Submitted 6 months ago

Were was the setting out engineer???
Or as the old saying goes measure twice!!!

(No subject)

Submitted 6 months ago

Where was the building control. It is better to make a mistake before the houses are built.

Webmaster note

Submitted 6 months ago

All comments posted at an earlier date to this one have been transferred from our old website.

Add new comment

This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Sign up to the building bulletin newsletter

Over 48,000 construction professionals have already signed up for the LABC Building Bulletin.

Join them and receive useful tips, practical technical information and industry news by email once every 6 weeks.

Subscribe to the Building Bulletin