News / Events

Wednesday, 29 April 2020

Limited Access Foundations

If you have ever designed a home extension, new build, or a foundation upgrade in places with limited access, you will understand the logistical nightmares involved with removing muckaway, navigating machinery through tight corridors or the risks in excessive manual handling.

The foundation is probably the most important part of the whole build, so adding obstacles in the way can be expensive, time consuming and frustrating. Without solid foundations the rest of the build is at risk, and like most errors, errors in construction multiply the further you go through the process. Unfortunately, to compound matters, foundations are also a big “unknown” - you might only find out what soil you’re dealing with once you start digging.

It is not unheard of to dig a strip foundation to a metre deep, only for the Building Control Officer to insist on - at least - another two metres. Hand digging is slow and expensive and can only go to 1.2m before you require shoring to make the dig safe. Therefore, anything that hampers large digging machines, or requires all of that soil to be manually walked through a family home, can be make or break for a project.

But what exactly constitutes "limited access"?

A simple terraced house is by definition inaccessible from either side, with the only way to get machinery and materials in without entering the house is through a back gate - if there is one - or over the roof - if there are no overhead power lines.

In cities, especially London, it is not simply the addition of rear extensions that can be obstructed by limited access. As the city grows, people require more and more ingenious methods of gaining space, meaning that foundation upgrades could be required in cellars and basements.

Undeveloped land, such as a forestry, is - fortunately - not a common area for residential foundations to be placed, but with the requirements of monitoring stations or mobile phone masts, it is certainly not unheard of for there to be a foundation requirement in a remote and inaccessible location.

Forests aren't the only natural land feature that might unexpected require foundations. River banks, especially those with retaining walls, are often only possible to reach from a pontoon or raft.

Taking all this into account, a limited access foundation requires a solution that is compact, lightweight and requires very little muckaway or mess.

Target's Heli Pile system is an aluminium mini pile that is installed purely on hammer action. With its largest piece of installation equipment being a 60kg post driver, it means that anywhere a person can walk, the Heli Pile can be installed.

Heli Pile is typically capped with less than 0.1m³ of concrete - or can even be concrete free - minimising the amount of mess and manually handling on site.


Limited Access Foundations is Target's latest webinar. Sign up to a session now for more information about problems that limited access can cause, and how these can be overcome. A question and answer session takes place at the end of the session, where you can ask the experts questions about your project.