General structural advice needed please

[SilverShadow]

Hi there,

 

My 1st post on the forum, and hoping you guys can help with our quandary please 🙂

 

My partner and i are looking to purchase a house, and our lvl 3 RICS survey has highlighted the potential for needing structural rework (sloping floors, cracking in interior plaster, some vertical mortar cracks in brickwork). From the checks we've had (Struc Engineer report & drain survey), it seems as though the waste sewer running alongside the house has failed in several areas, though there might also be some ground movement (can't yet tell if the subsidence is from soil erosion from drains, or ground, or both). Obviously we'd get a more detailed structural analysis if we proceed, but wanted to gather a few initial thoughts from anyone in the know.

 

Our questions are around the following:

 

1) I've read that resin injection with geopolymers can be a cheap & effective alternative to underpinning - just wondering if anyone had used this & what their thoughts were (we're thinking of using Geobear, unless anyone can recommend a better UK company)? Have heard it's around £1200/metre....

 

2) When using something like this, are there any implications if we decide to build a house extension over/around that area at a later date?

 

3) I've read that house structural rework can cause problems with insurance & resale value. Apparently, resin injection avoids this, as it doesn't 'break the ground', hence no need to declare it. Does anyone know more about this claim of avoiding the insurance/resale issue?

 

4) Does anyone know what is classed as 'structural repair' that may affect the house value/insurance? Eg, if we use helibars to repair the brick mortar cracks will this need to be declared or just part of the normal process of house repair?

 

5) Any other advice/tips/gotchya's from anyone who's experienced similar when fixing their property

 

 

Many thanks for you help - totally appreciated

Mark

Edited November 13, 2022 by SilverShadow

[Mr Punter]

The Geobear Google reviews do not inspire confidence.

 

Unless the property is at a huge discount (at least twice the cost of proper underpinning, drain replacement and crack repairs) I would not go ahead.

 

 

[nod]

1 hour ago, Mr Punter said:

The Geobear Google reviews do not inspire confidence.

 

Unless the property is at a huge discount (at least twice the cost of proper underpinning, drain replacement and crack repairs) I would not go ahead.

 

 

Good advise 

 

I would add  If you really want this property Assume the worst and base your offer on this 

Houses with subsidence issues are usually money pits But not always 

[Gus Potter]

4 hours ago, SilverShadow said:

My 1st post on the forum

Top stuff and welcome.

 

I've made a few comments below which will I hope will help.

 

First things first. In the past I have bought and sold properties that are suffering apparent distress. Mostly now I do a bit of design for Clients that are interested in these types of "distressed" properties, some buy them to "sort out" and sell on, some buy as they are cheep and turn them into their "forever home". Both are fascinating for me as a designer as I often get involved right from day one and see the project through to the the end.

 

Now there is no free lunch here. Much depends on your attitude to risk and MOST importantly how much work you are willing to put into researching the problem, understanding it and identifying cost effective solutions, if there are any. Some can be stunningly simple and cheep to implement. Spotting this opportunity where others have missed it can be the key to unlocking it all. Making / saving money that let's you make a good profit or spend it on the things you want.. finishes etc or just make it affordable as a project when you are on a limited budget.

 

What I'm saying is keep your enthusiasm up!

 

A question. You mention the word "sewer" To the lay person this could mean just a drain that carriers water from say the toilet and maybe the roof from your house out into the street from your house alone. But in technical terms a "sewer" could be a big public asset.. a very big infrastructure pipe. You also have what is often called a public drain, that is a pipe that serves a few houses before it goes into the "sewer". Public drains are often more manageable.. but if you want to build over them later you'll need build over permission. This is often doable if you plan ahead for a future extension.

 

Your SE report will likely be an "observational report with some limeted technical comment" not offer up solutions and be heavily caveated. It's the solutions bit that cost the professional fee money as the SE has to step up to the plate and carry the can if it does not work out.

 

You mention various options.. underpinning, structural repair etc and how that is treated in terms of insurance and resale value. If you involve an SE to give you advise on solutions and thereafter design them up this should cover you as the SE carries insurance that should satisfy most folk... lenders etc and selling later.

 

Also you will need to involve the local authority who will provide a completion certificate. That also adds weight when selling.

 

Your project sounds really interesting. If you wish post photos, provide more info and you'll get loads of help and suggestions on BH. Try if you can not to reveal the location as it may be a live bid. If in doubt PM folk here.. but if you end up buying it then you should post about how you won the bid. And if you benefit from it you should make a donation to Build Hub!

 

If you don't get this one then keep your hopes up and look for the next as you'll learn loads on BH. I do every time I log on.

 

All the best.

 

 

 

 

 

 

 

 

 

 

 

Our questions are around the following:

 

1) I've read that resin injection with geopolymers can be a cheap & effective alternative to underpinning - just wondering if anyone had used this & what their thoughts were (we're thinking of using Geobear, unless anyone can recommend a better UK company)? Have heard it's around £1200/metre....

 

2) When using something like this, are there any implications if we decide to build a house extension over/around that area at a later date?

 

3) I've read that house structural rework can cause problems with insurance & resale value. Apparently, resin injection avoids this, as it doesn't 'break the ground', hence no need to declare it. Does anyone know more about this claim of avoiding the insurance/resale issue?

 

4) Does anyone know what is classed as 'structural repair' that may affect the house value/insurance? Eg, if we use helibars to repair the brick mortar cracks will this need to be declared or just part of the normal process of house repair?

 

5) Any other advice/tips/gotchya's from anyone who's experienced similar when fixing their property

 

 

[SilverShadow]

Hey guys - many thanks for your sage suggestions 😁

 

To clarify a little further - we do envisage this to be a 'do-er upper' project, as it'll hopefully be our forever house.

 

We've negotiated £37k off the original price (and have a total budget of £50k), so hopefully should have enough in reserve to address the main issues. Our survey highlighted around £17k of things to remedy, and we managed a further £20k off, to cover the structural side. The survey report was 100 pages, and although this has the making of a 'money pit' has hopefully identified the lions share of fundamental aspects

 

We opted for the mantra of 'buy the worst house in the best street', as we feel it's the best way to get our dream house for the right price (in the long run)

I perhaps described the sewer incorrectly - it is a private (100mm pipe?) drain for waste (sink, toilet, etc), rather than shared, and old clay pipes almost 100 years old. The house is a 1930's 2 storey semi, and most likely has shallower shale foundations, which on a hill is potentially why we see these structural issues. It also explains why there are 4 or 4 failures along a 6 meter strip along the house.

 

The brickwork cracks are about 4 or 5 ft, as shown in the pic below - we are hoping resin injection will help close this and then repoint/helibar to resolve the problem

 

 

Regarding Geobear - i'm a little surprised more people haven't used a company like this. They seem fairly legit (have good reviews on Trustpilot) & are a multi-national company running for 40 years that undertake many industry/commercial projects (airports, trainlines, etc), so i'd expect the product to be up to the job. The product is designed to last 100 yrs, and guaranteed for 10yrs. We may opt for a private SE to oversee this, but they seem to imply they will take care of everything their side, so wasn't sure if it was extra unnecessary cost. We also weren't sure what we'd need in terms of sign off/assurance to ensure all regs are compliant and we have no insurance/resale issues (should we later move)

 

Out of interest, can anyone recommend a good SE around the East Midlands, and what sort of rate £/day would we expect if we opt to employ one while the work is undertaken?

 

Many thanks again - happy to post more if folks wish

Mark

[George]

What did the SE report recommend?

 

I've never specced the polymers but have had various CPD lunches off them over the years. I've always had the impression they're done when nothing else is really suitable, so I would certainly look at conventional cement grouting or even if underpinning before opting for polymer injection.

 

2) Shouldn't be significant. May need to do a raft rather than normal footings but all achievable 

 

3) If done properly, shouldn't be an issue. A ASUC registered contractor is a safe(r) bet

 

4) Not for normal repair. Crack stitching isn't always needed and can be counter productive on an old house. I wouldn't crack stitch the photo above

 

 

[Jilly]

Just to help you understand the process: We commissioned an SE to give a solution with instructions/diagrams etc (which are submitted to Building Control for them to check) and then the builder/other carries it out and it's inspected by BC and signed off. We had an SE visit initially and at points where we needed some advice.

 

If you don't like/agree/want to carry out that suggestion, you could ask for another solution, or even (rarely) ask another SE for a second opinion to find a different remedy. 

 

This removes the danger commissioning a company (who are not unbiased and independent) to do work which you or they have diagnosed.  However, they might have their own engineers to do the drawings which you would give to BC. 

 

PS you need different house insurance whilst you do remedial works, you might even have to keep the original householder's insurance co as other co's may not want to take it on. 

Edited November 14, 2022 by Jilly

[SilverShadow]

Thanks again guys - all very invaluable

 

I feel with Geobear, they are only just coming onto the radar of doing residential properties (normally it is large scale projects). I think many do not recommend them, as they are not well known. But we picked up on it when the vendors SE report mentioned them as an alternative to traditional underpinning (which we are keen to avoid, due to the stigma it carries for buyers). We are hoping the house will hold value though, as subsidence in that region is not mainstream yet not unheard of either

 

However, i think the idea of a SE to either give initial analysis / review and sign off the ground resin/underpinning seems like sound advice. There are long cracks in probably half the rooms in the house (some the length of the ceiling, but most only 1mm or so wide), which i'm convinced are the result of the foundations, rather the roof bowing

 

Here's a bit more of an idea of the cracking we see inside (and we also noted the front upvc door is 'sticking' - another sure sign of subsidence). This pic shows one of the worst plaster surface, and most cracks are around 2mm wide (some slightly smaller, some wider). I've left one encircles in A, so you an see them 1st hand

 

 

PS - does anyone have any good SE recommendations around East Mids, or know where i can find some (perhaps there is somewhere on here....🤔)

 

Edited November 14, 2022 by SilverShadow

[saveasteading]

Firstly, i am  both Engineer and contractor. 

For a clientI I take few risks.

For my own, and family, i take more chances. We have taken on severely distressed buildings 5 times, always to live in. In every case there have been nasty surprises, even to me. These would nof have come up in reports other than as general warnings.

 

More accurately these are considered decisions, not risks.

 

So the default here is to say to be careful. The discount may not begin to cover the risks....but i don't know as i don't know enough about this property.

 

If this house was possibly to be mine i would cost the repairs of the known problems, but also allow for the unknowns.

Repairing to live in rather than sell is an advantage. Things like the drains can be dealt with as and when.  A builder either has to get it right, or disguise the problems, in order to sell it.

 

Stitching is a repair, not a solution. Best have an expert look at what caused these cracks and the floor movement.

A good local SE could simply have a walk round inspection and give off the recird advice. This works for easily seen problems and avoids unnecessary detail and report cost.

For example i once suggested this, on the basis that the SE would say only whether the house would get a mortgage, and why not. Client paid for 2 hours and avoided an expensive mistake.

 

The discount may not be remotely enough.    Be prepared to let it go.

 

On a positive. Maybe the ground is ok and thd floor is just very badly made, and can be repaired. Maybe the walls are cracked for other ressons thsn foundations, and just need repair.

On a negative....often houses are beyond repair, demolished and rebuilt as new.

Be careful, get independent professional advice.

[SilverShadow]

Many thanks again.

 

The vendor did get their insurers to hire a SE company to perform a report, based on a visit. Their report highlighted the following:

 

External:

The cracks observed appear to be due to thermal movement, settlement of foundations and
potentially defective underground drainage.

 

Kitchen/Bathroom floors (bathroom is above the kitchen):

The sloping and uneven floors
appears to be due to historic and/or active settlement and timber creep

 

General:

• The property appears to be structurally stable but is in below average condition
• Underpinning, Geobear or similar works will be required, if cracks re-appear after helical
• bar installation.
• A CCTV is recommended to check the condition of the underground drainage system
• Sloping/uneven floors can be removed and replaced once any cause of drainage
• failure/subsidence has been rectified

 

The drain CCTV did identify places where the clay pipes had moved to expose a few clear gaps for water to leech into the soil, so we envisage this will be a main factor, though have no expertise as to how much a leaking drain would feasibly create holes big enough for the foundations to sink.

 

Overall, our budget for shoring up the foundations is around £15-30k(ish), which we'd hope would cover most if not all of the rework along various points of the 8m house sidewall.

 

Our surveyor costed £17k on other items identified in the survey, and as mentioned we've also allocated up to £33k for structural rework, but overall wary of whether a repair budget of £35-50k would typically cover enough to make it viable.

 

We are very much on the fence with the house - it's not a ramshackled heap of bricks by any means & we're not afraid to find problems, but also quite aware it hasn't been 'loved' for many years & appreciate it might need lots of work in several key areas

 

 

 

Edited November 14, 2022 by SilverShadow

[Dave Jones]

37k not enough. buyers market with the recession. I'd want double that at a minimum.

[saveasteading]

So the vendor's insurers are aware, and have commissioned a survey which says that the foundations have failed, but are not paying to repair it, and it us up for sale.

Hmmmm.

 

Any more info on this?

Would you get any insurance that was worth having? Mortgage, probably declined too.

Edited November 14, 2022 by saveasteading

[SilverShadow]

Our concern is that asking for £75k off, the buyer would probably just go via 'We buy any house'? 🤔

 

We agreed the price in Aug/Sept, while the market was more buoyant, so thought £37k seemed reasonable, although in hindsight it is probably expensive now (although prices in that area are holding up and typically £40-60k more, for what seem to be houses in better repair). The vendor is keen for a quick sale, due to financial concerns (house unoccupied & paying rent till the sale goes through to provide money for their new house), and so won't spend months trying to have this sorted

 

We have our mortgage secured, as it is small enough to not matter (we have informed them of the potential for this work). Our insurance may well be a concern (we may have to get insurance that doesn't cover subsidence, or pay a premium to include this).

 

Our basis that this resin injection seems to tick the boxes for main concerns regarding resale/insurance, etc (as per bottom of this weblink):

https://www.geobear.co.uk/subsidence-repair/

 

Although that of course doesn't take cost into account. It is my theory that the house is still undergoing movement - perhaps it is the factor of 'taking in more on a second viewing', but i believe some cracks are still opening (there was a 2 month gap between viewings)

 

 

We love the house & the locality, but the structural aspects & vendor are our main reason for hesitancy. Looking on Rightmove, we know we wouldn't find anything as good in that location for that price

 

 

Seems like most folks would give this a wide berth, which is probably what we'd have already done, if it weren't for the our love of the property & its situation. Eternally grateful for all your thoughts

Edited November 14, 2022 by SilverShadow

[SteamyTea]

Just had a quick look at Geo ear's website.

Two things would concern me.

Seems they are using an expanding polymer, probably a polyyrethane.

The other is the use of the word 'leading' in their blurb.

I worked for the leading supplier of saunas, steamrooms, spa baths and sunbeds.

We joked that it meant we made mistakes and the customers paid for them. 

[SilverShadow]

Thanks again for your input all 😀 

 

I would perhaps hazard a guess that some folks may not have come across this groundwork technique before, and so rightly cautious as to its suitability?

 

If we go ahead with the purchase I think it'll be the method of choice, as I'd much rather it than digging under the house while propping it up 😬

 

Many thanks for your time - please feel free to contribute further, as I will keep an eye on the thread a while longer

 

 

 

Huge thanks

Mark

 

Ps - i'm interested in hearing from anyone who has experienced using geoploymers on their property or commercial buildings, to gather their thoughts

[SteamyTea]

May be worth reading up on Jet Grouting as this seems to be a modification of it.

 

https://theconstructor.org/geotechnical/jet-grouting-procedure-advantages/14470/

[Dave Jones]

if an insurers SE says the footing has failed then any 'resin' is literally paving over the cracks. It sounds like your looking for an easy out to justify the price and have latched onto this. 

 

Underpinning is not a massive job and will fix the root cause. 

 

Webuyanyhouse wont touch it with a bargepole as they wont be able to flip it with subsidence which is all they do.

 

stick by your guns there is always another place.

[SilverShadow]

Thanks guys - it is great to gather a consensus of opinions....😉

 

May i ask, for those with reservations about geopolymer/resin injection, is there anything substantial to base your hesitancy on please?

 

It's not that i doubt per se, but would like to know how a multinational company like this can operate successfully for so many years, if their product is essentially inferior? When i've read several independent articles they all mention this technique as a viable/cheaper alternative to underpinning, so i must be missing something fundamental in terms of why it is a non-starter....

 

Is there a fundamental flaw in my understanding, or are folks reservations based on it being a relative unknown? 🤔

 

Apologies for labouring the point - it is the preferred method we'd like to adopt (if we buy the property at all), so wanted to really get into understanding the reasons why this is so unsuitable

 

Thanks all

Mark

Edited November 15, 2022 by SilverShadow

[ProDave]

13 minutes ago, SilverShadow said:

It's not that i doubt per se, but would like to know how a multinational company like this can operate successfully for so many years, if their product is essentially inferior? When i've read several independent articles they all mention this technique as a viable/cheaper alternative to underpinning, so i must be missing something fundamental in terms of why it is a non-starter....

Are you / they saying their product will stitch a crack in the brickwork back together in such a way that underpinning will not be required?

 

Surely if the foundations have subsided and there is further movement, all that will happen is the brickwork will crack again at the next weakest point, probably the next brick along?

 

I can see this being a structural cure for historic settlement where the cause of settlement has been fixed and it has been confirmed there has been no further movement, but you don't know that now do you?

[markc]

Without digging (no pun intended) for information on the product/process, am I right in thinking this is a soil stabilisation process by injecting a “substance” that then solidifies?  If so then I would be very sceptical for future insurance or mortgage purposes as it is effectively underpinning.

[SilverShadow]

Quote

 

Are you / they saying their product will stitch a crack in the brickwork back together in such a way that underpinning will not be required?

 

Surely if the foundations have subsided and there is further movement, all that will happen is the brickwork will crack again at the next weakest point, probably the next brick along?

 

 

 

Good question, and i'm only basing on my understanding (though i could probably apply for a salesman job at this rate! 😅)

 

The resin is injected into the ground at high pressure - this seeks out the gaps/fissures in the soil voids and fills up. Once in there the resin expands, effectively lifting the base of the house close to it's original level, and sets solid in a matter of hours. The whole process is meant to take a few days, and by all accounts has been used on a number of commercial applications (motorways, airports, railways, commercial building, judging by their testimonials), and i would imagine in those cases some of those may have unstable ground with minimal foundations. Once raised 'the theory is' the cracks have reduced, but will still need repairing, just like i'd imagine they would with concrete underpinning? 🤷‍♂️

 

As i understand, it's well known that concrete underpinning is more expensive, takes longer, more intrusive & can carry a 'resale' stigma according to mortgage providers/estate agents.

 

Apologies guys - i am probably too hung up on this structural option. If it is unfeasible we simply won't purchase the property

Edited November 15, 2022 by SilverShadow

[markc]

I’ve seen injection done under large slabs to re level and it worked well (drive and pathway). But it is still under pinning but without the tried and tested methods of excavate and replace with known quantities of concrete and bearing dimensions etc.

I’ve been involved on some big stabilisation projects but I would not use this under walls etc as the bearing surface etc. is unknown. Yes it might work, but for how long? 

 

[SteamyTea]

24 minutes ago, SilverShadow said:

this seeks out the gaps/fissures in the soil voids and fills up

Do you know where the gaps and fissures are on this property?  Or if that is even the problem.

 

25 minutes ago, SilverShadow said:

by all accounts has been used on a number of commercial applications (motorways, airports, railways, commercial building, judging by their testimonials)

Totally different problem.  Spending a few thousand (or even a few 100,000) on a multi million project is not the same as spending a few thousand on a house. 

I have a feeling that large warehouses are build to different safety standards than houses, maybe @saveasteading knows as he deals with large buildings.

[SilverShadow]

Thanks guys - enough food for thought to give me indigestion!

 

All comments are highly valued, and i hope me challenging your opinions is not perceived as undervaluing your experience. I probably haven't articulated my question very well earlier, so it may have come across as 'bias'.

 

What i was really after is:

"why not to choose geopolymer/resin injection, based on others experience/knowledge of using it"

 

rather than

"Why traditional underpinning is option to choose"

 

 

 

Apologies for not making myself clearer earlier....

 

 

[SilverShadow]

1 hour ago, markc said:

I’ve seen injection done under large slabs to re level and it worked well (drive and pathway). But it is still under pinning but without the tried and tested methods of excavate and replace with known quantities of concrete and bearing dimensions etc.

I’ve been involved on some big stabilisation projects but I would not use this under walls etc as the bearing surface etc. is unknown. Yes it might work, but for how long? 

 

 

 

Thanks for sharing your experience, MarkC - i'm not sure, but definitely something i need to consider.

 

As regards lifespan, from what i gather these resins are guaranteed for 10-20years (depending on manufacturer), and read somewhere they last around 100 years (stability tested up to 60 years).

 

......according to their blurb, of course!

Edited November 15, 2022 by SilverShadow