Material Analysis - Mortar

isnottheword

If I wanted to get the mortar between block courses on a cavity wall analysed for sand/cement ratio;

1. Who can do that?

2. How long does it generally take to get results?

3. Rough cost?

4. Is there a definitive guide as to the acceptable parameters for the constituency of mortar? i.e. do the building regs outline an acceptable range? Dwelling in question was completed in 2006 - so subject to the building regs that were in place in the lead up to that point.

mickeypat

Why do you want to test the mortar?Cracks?

isnottheword

mickeypat wrote: »

Why do you want to test the mortar?Cracks?

Yes.

Gumbo

isnottheword wrote: »

If I wanted to get the mortar between block courses on a cavity wall analysed for sand/cement ratio;

1. Who can do that?

2. How long does it generally take to get results?

3. Rough cost?

4. Is there a definitive guide as to the acceptable parameters for the constituency of mortar? i.e. do the building regs outline an acceptable range? Dwelling in question was completed in 2006 - so subject to the building regs that were in place in the lead up to that point.

The mortar in the wall joints imo would come under Oart A (Steucture) and Part
D (Workmanship). The mortar should be mixed in accordance with the manufactures guidelines or engineers specification for the wall in question.

Be a rough one proving liability now as the statue of limitations for Building Control is only 5 years.

isnottheword

kceire wrote: »

The mortar in the wall joints imo would come under Oart A (Steucture) and Part
D (Workmanship). The mortar should be mixed in accordance with the manufactures guidelines or engineers specification for the wall in question.

You'll have to forgive my lack of knowledge on the subject. So if mortar mixed on site - sand/cement - is there not an indication of minimum ratios/strengths, etc? Mortar is a generic substance mixed on site is it not - so what manufacturer?

kceire wrote: »

Be a rough one proving liability now as the statue of limitations for Building Control is only 5 years.

Statute of limitations is not an issue - the clock is stopped ;-)

mickeypat

isnottheword wrote: »

You'll have to forgive my lack of knowledge on the subject. So if mortar mixed on site - sand/cement - is there not an indication of minimum ratios/strengths, etc? Mortar is a generic substance mixed on site is it not - so what manufacturer?

Statute of limitations is not an issue - the clock is stopped ;-)

The foundations would more than likely be the fault here imo

isnottheword

mickeypat wrote: »

The foundations would more than likely be the fault here imo

Yep, appreciate the input but founds are not implicated in this instance.

mickeypat

isnottheword wrote: »

Yep, appreciate the input but founds are not implicated in this instance.

What exactly is the problem?

isnottheword

mickeypat wrote: »

What exactly is the problem?

Horizontal cracking running along mortar joints at various levels in the external walls. It's led to water ingress.

I'm confident that foundations/subsidence are not at play. I want to ensure that the constituency of the mortar is not a factor.

Johnnyhpipe

Hi,

From my own experience as a structural engineer I have not yet come across horizontal cracks occurring as a result of mortar inconsistencies/quality etc. Many horizontal cracks are a direct result of foundation settlement often occurring simply due to a blocked/damaged drain nearby - but as you say that's already been ruled out.

I would be surprised if it was the mortar considering that blocklayers were mixing fairy liquid into in on some poor celtic tiger era sites (!!!) which have not cracked to the extent yours has. That said, get it tested by all means. Contact BHP labs. I would look for say compression tests and material analysis. Worth taking another look at possible settlement though.

Incidentally, is the wall perfectly plumb? Any other cracks, diagonal or vertical?

isnottheword

Johnnyhpipe wrote: »

Hi,

From my own experience as a structural engineer I have not yet come across horizontal cracks occurring as a result of mortar inconsistencies/quality etc. Many horizontal cracks are a direct result of foundation settlement often occurring simply due to a blocked/damaged drain nearby - but as you say that's already been ruled out.

A blocked or damaged drain? What type of a drain? The only 'drain' closeby is a sewage outlet that runs along the side of the house - out into the mains sewerage system in front of the house. It's always functioned whilst I've lived here (10years+).

Johnnyhpipe wrote: »

I would be surprised if it was the mortar considering that blocklayers were mixing fairy liquid into in on some poor celtic tiger era sites (!!!) which have not cracked to the extent yours has. That said, get it tested by all means. Contact BHP labs. I would look for say compression tests and material analysis. Worth taking another look at possible settlement though.

Yes, and that's the current professional thinking on the matter. However, I only get one opportunity at this. Once repairs are done and the insurer walks away, they wash their hands of it.
It's with that in mind that I am thinking it's worthwhile going to this expense (I guess depending on what expense is involved...) and effort...

Johnnyhpipe wrote: »

Incidentally, is the wall perfectly plumb? Any other cracks, diagonal or vertical?

Walls are very close to plumb. Some other cracks - vertical - but very much the exception rather than the rule.


Thanks for the info - ref. BHP. I'll contact them and get further detail.

Johnnyhpipe

Is all this based on what the insurer's engineer has stated in a report? If so, then Monday morning engage your own structural engineer to review/report on this. They can prescribe testing/opening up works if needed and from there can establish fact. The great thing about fact is - its true whether your insurer wants to believe it or not!

I don't do insurance work myself but have dealt with insurer's "engineers" in the past and have had to prepre reports to counter their nonsense arguments on numerous occasions.

isnottheword

Johnnyhpipe wrote: »

Is all this based on what the insurer's engineer has stated in a report? If so, then Monday morning engage your own structural engineer to review/report on this. They can prescribe testing/opening up works if needed and from there can establish fact. The great thing about fact is - its true whether your insurer wants to believe it or not!

Johnnyhpipe wrote: »

Is all this based on what the insurer's engineer has stated in a report?

I can't accept a single thing my insurers /their engineers state

Johnnyhpipe wrote: »

If so, then Monday morning engage your own structural engineer to review/report on this. They can prescribe testing/opening up works if needed and from there can establish fact.

Yes, I have done. Notwithstanding that, my own engineer can't be 100% confident of the root cause. A high degree of confidence (and I'm not an engineer - but I have listened to the points in terms of reaching that conclusion and it sounds plausible to me) is the best he can offer.

I guess my objective here is to close out the potential for blowback even further. The time is now in terms of getting matters addressed. If another issue arises after site works, the chances are I'll be on my own.

Thanks for your input. I'll contact BHP and see what they can do/what they charge, etc. If not prohibitively expensive, I'll run with it - just for peace of minds sake.

mickeypat

Most insurance engineers are full of ****, a well know slate maker sent an engineer out to chech my uncles faded slates and tried to fob him off saying the cramping's were too tight ffs.Needless to say he was told where to go. A few days later after a call from my uncles solicitor they called to say they'd pay for the replacement of the old slates and admitted they were churning out slates too fast.

isnottheword

The (structural) insurer reckons they have no knowledge of 'construction details on my property'. That in response to my request for confirmation as regards who was the block supplier on the development and ditto ref. the supplier of the bonded bead infill cavity insulation (I asked them for the agrement cert).


Their recommendation is that I contact the applicable local authority.


Surely, they would have mitigated their risk via receipt of full details on what products were used?


Am I being fobbed off here or should they have detailed information on file for all of these items?

Johnnyhpipe

Completed 2006 so its a classic celtic tiger house. Id be surprised if anyone had any records!

isnottheword

Johnnyhpipe wrote: »

Completed 2006 so its a classic celtic tiger house. Id be surprised if anyone had any records!

it wouldn't surprise me at all if they don't have them. The more pertinent question is should they have had them (and still have them today)?


What's the likelihood that the County Council Planning office would have such detail? I wouldn't imagine they spec'ed it right down to the specific block supplier? Same with Bonded Bead Cavity product.

My concern here is if I go to the expense and trouble of having blocks tested, what basemark do I test it off in the absence of knowledge of the supplier and their declaration of performance?

Johnnyhpipe

The council won't have any such detailed information, nor would they be expected to.

The insurer has likely insured the property on the basis of opinions of compliance provided by tye design team. Unlikely they even care what spec block was used.

Horizontal cracks in the walls....I'm still not convinced mortar/blocks are to blame. Lets say you found that the blocks/mortar are for some reason, weak. Unlikely anyway, but what then?? Has your engineer suggested a suspected cause/solution at this stage?

Even if they were weak (unlikely) how would this explain horizontal cracking in a wall panel..? 99% of the time its settlement/damaged drains.

Gumbo

isnottheword wrote: »

it wouldn't surprise me at all if they don't have them. The more pertinent question is should they have had them (and still have them today)?


What's the likelihood that the County Council Planning office would have such detail? I wouldn't imagine they spec'ed it right down to the specific block supplier? Same with Bonded Bead Cavity product.

My concern here is if I go to the expense and trouble of having blocks tested, what basemark do I test it off in the absence of knowledge of the supplier and their declaration of performance?

The design team should have them tbh. Most decent offices kept their records long after the minimum requirements.

When I was in private practice, we had an off site storage shed with every job file from 1979 (company founded).

The planning department will have the physical file in storage as they are required to. They may not have any of the specifics as it's not required for planning, but you may be lucky in that the planner requested a sample of the brick to be used and then the developer would have supplied a sample along with the manufacture and style which might lead you somewhere?

isnottheword

kceire wrote: »

The design team should have them tbh. Most decent offices kept their records long after the minimum requirements.

When I was in private practice, we had an off site storage shed with every job file from 1979 (company founded).

'Design team' long since dead n' buried immediately after the Celtic Tiger bombed.

I'm just talking in terms of regular blocks - so I doubt the council planning needed a sample of same.


Should the declaration of performance not be very similar between suppliers of bog standard concrete blocks?

Metric Tensor

Yup. The DoP would be almost identical and the "bog standard" concrete block had been targetting the same strength for many years. This was 5N/mm2 (this is now 7.5N/mm2 but the block is the same it's just that a different testing standard is used that reports the strength differently). In layman's terms these were called "5 Newton Blocks"

It would be quite easy for the blocks to be tested to see if they meet this standard - but I would be almost certain they will.

N.B. Stronger blocks can be and have been used in certain circumstances (i.e. 10N, 15N, 20N).

mickeypat

Its 100% the foundations thats the problem, not the blocks

Metric Tensor

Can you post pictures OP.

There's a phrase: "nothing new under the sun" - there's an very good chance someone who frequents this board will have seen something similar before.