Insulated Concrete Formwork Help & Advice

Our insulated concrete formwork help & advice centre has been created as a reference and information hub for designing and building ICF structures in general, and Polarwall in particular.

Insulating Concrete Formwork Basements

When You Should Always Consider a Basement 

More and more builders consider a basement. The requirement for living space and the planners generosity in allowing what you might need are not always in alignment.  If you can’t use your roof space and you have to have that cinema room or gym or snooker room then a basement will be needed.   

Basements are great for noise reduction so party rooms, home cinemas, music rooms or recording studios are ideal for inclusion in the basement design. 

When You Should Always Consider a Basement 

Maybe you would like a pool for year round swimming?  A basement can be an ideal place for a pool and we have many of these in our past portfolio. 

A basement is excellent for staying warm in winter and cool in summer due to the insulating and stabilising effect of the surrounding soil.  Having a basement in your plans can make it easier to achieve your home energy targets. 

A basement can provide great security for family members and for your possessions too.  In the UK we don’t (yet) have the extreme weather conditions that other countries have to think about.  Climate change may alter our needs here but even without weather extremes, a basement is the safest place to be when conflict strikes a country.  Since Putin’s Russia invaded Ukraine and the nuclear option was being discussed, we have seen about a 50% increase in secure basement enquiries.  Trouble is, that if this conflict should expand then it is probably too late for these people to benefit from a basement.  We need to be planning for the unexpected catastrophes before we know they may

Some sites are calling out for basements.  The most obvious being the hillside plot.  Sloping ground usually requires stepped footings. These are far more expensive to construct that an ordinary level footing.  In this circumstance digging into the slope to create a “walk-out Basement” makes perfect sense.  Such a walk-out basement has the following advantages: 

  1. only about half the dig out of a full in-ground basement  
  2. Great for allowing natural light into the basement especially with a walk out patio. 
  3. It can be easily drained from the outside so a dream for staying dry. 

Some sites have excellent drainage  

Your land cost and building footprint should dictate how you maximise the size of your plot and whether a basement should be in your plans.   High land cost for a smaller site and a basement might be the ideal space creation solution.   

when you should always consider a basement
Polarwall Basement

However, in tight city sites where adjoining properties are close to your proposed basement dig, then you need to speak with a structural engineer before you even think about an architect.  The last thing you want is your neighbour’s property sliding into your hole in the ground.  The way to stop this disaster is usually with contiguous piling or underpinning solution.  Both of these options are potentially very expensive and will add a significant amount to your budget.  However the end result can certainly be worth it.

It is a good idea to involve a builder experienced in building basements, below is a link to a midlands based builder who has worked on many projects with us.

Midland New Homes

Find out more about When You Should Always Consider a Basement. Get in touch today.


The various sections above cover the main topics for Insulated Concrete Formwork (ICF) construction both above and below ground. 

Do not use this as an alternative to what your chosen manufacturer recommends.  We can do things with Polarwall that ICF blocks can’t do and there may some things that you do with other ICFs that Polarwall can’t do. For example our instructions on vibrating the concrete may not be wise on some EPS block systems. 

We want to add to and develop this section, so we welcome all your questions, suggestions for topics and feedback.  If you want to go deeper into a topic please let us know.  This advice hub does not replace our training (or any other companies training) and you still need to avail yourself of our FREE training course.

Have a question or suggestion not listed here? Feel free to contact us