Waterproofing Wisdom – Episode 09 Basements & Major Refurbishments

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Is net zero carbon shaping the market?  We think so! 

Indeed, achieving net-zero carbon emissions is significantly shaping today’s markets. We think there’s a drive coming from  Environmental Social and Governance (ESG) reporting major corporations’. 

This increase in major refurbishments (re-using concrete foundations) is highlighting some waterproofing considerations.

A good independent waterproofing consultant will be able to deliver great value on a refurbishment scheme through:

  • Assessment of the waterproofing performance (i.e. a comprehensive condition survey)
  • Consideration of the future required waterproofing performance and engage the design team on changes that could reduce the need for waterproofing (e.g. site durable spaces like cycle storage at the basement perimeter)
  • Early delivery of a Waterproofing Design Philosophy to assist in understanding of spatial arrangements, gross internal area, project budget and programme etc.

Often, design development teams completely underestimate what’s going on with waterproofing and how that’s going to impact program. If you’re doing a refurbishment scheme on a project with a basement we commend to you the value of good quality independent basement waterproofing advice.

You can watch a 6 min video here.

Waterproofing Wisdom Episode 9 – Basements & Major Refurbishments 


Ben Hickman
Technical Director

Hello and Welcome to Waterproofing Wisdom Episode 9. My name is Ben Hickman, and I am the technical director of CLW, I love waterproofing and today I wanted to talk to you about basements and major refurbishment schemes

I wanted to share with you some three-letter words. Is net zero carbon shaping the market? yes, it is and then here are some three-letter words E S G which stands for Environmental, Social and Governance and that is one way for large corporations to think about their  impacts on the world and how they do things similar to CSR (Corporate Social Responsibility) apologies if I’m getting this completely wrong this isn’t my specialism

But my understanding is that if you are a large corporation and you want to attract investors part of what you need to do is tell the world we care about the environment and part of how you would do that is by only leasing environmentally friendly offices and part of how you would do that is choosing an office which has a good EPC.

Now as of April this year, a bad EPC is you cannot legally lease that to a corporate entity anymore If I understand it correctly, I’m not talking about quite that bad on the EPC rating but if you’re a big global corporation and you want to tell your investors look we’re good people we care about the environment part of how you would do that is by thinking about renting an office building that has good environmental credentials.

So that would look like a good EPC rating but it would also look like a good BREEAM rating and that would mean one way of achieving that would be to refurbish an existing office building bump up the thermal performance and make it look nicer in a much more attractive place to be, but you would want to save all of the embodied carbon that’s already there or as much as you can so 

Now if you have a large office building in the centre of say London that probably already has a basement and when you refurbish that you’re going to want to use that basement it’s part of your embodied carbon you wouldn’t want to rip it all out and start again and we’re seeing more of that in the market now than we used to where we’re being asked to comment on refurbishment or be part of a design team on a refurbishment rather than just the good old new build dig it up and do something new.

So why does that matter it matters because we see day in and day out design development teams completely underestimate what’s going on with waterproofing and how that’s going to impact the program and so earlier this week we issued our report on a refurbishment scheme where the basement floor slab is just mass filled concrete and it’s  cast in bits and they don’t have enough headroom to put a cavity drain membrane in

And so really the only viable option is going to be to effectively underpin and dig down in the basement that hasn’t been allowed for in the program hasn’t been allowed for in cost it’s going to have big implications and it’s come about by somebody just not knowing enough about waterproofing perhaps  getting some basic input from a supplier who’s very keen to sell  them their products but they haven’t thought it through

So my appeal to you is if you’re doing a refurbishment scheme on a project with a basement get good quality independent basement waterproofing advice and that sort of company like ours would assess the current waterproofing performance and think through what is going to be a good enough waterproofing performance if the burst water main happens outside consider what future waterproofing performance is needed and then we would come up with a design philosophy this is how we’re going to do it you want to know that early because it could impact another three letter word GIA (Gross Internal Area) that can affect your funding and the value of your development.

So the other way we can help development teams think things through is, can we relocate that, that needs to be very dry, let’s move it away from the perimeter wall bike store could be a little bit wet we can put that on the struck concrete that currently looks dry and it’s a little bit safer so we can help design teams think that through.

My personal goal for 2023 or one of them is to achieve a handstand push-up. I do not have that kind of physique, but I have been working hard at handstand push-ups for a good nine months now and I still can’t do a handstand.

I finally decided to find a personal trainer or somebody who knows what I am doing wrong and who can help me. I went to see that person today, I spent an hour stretching and a whole bunch of stuff then suddenly I could nearly do a handstand and I couldn’t yesterday.

It helped me realise the value of good advice at the right time and I would encourage development teams, architects, engineers and project managers to work smarter and avoid messing up your program and your budget by getting waterproofing design input earlier

Thanks for watching if you ever want to talk through basement waterproofing or any waterproofing for that matter please do get in touch

Thank you

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