Problem with exterior render where plinth and wall meet (timber frame bungalow) causing condensation on interior skirting boards

[Naoma]

We recently bought a small timber frame bungalow, which requires some repairs to the exterior render, as there is damaged to the section where the plinth meets the wall, I have attached pictures of the area. Unfortunately, so far we could not find anyone, who could offer use an explanation or solution to the problem.

 

As seen on the picture attached the grey tape (which seems to be some sort of flashing tape) is broken and coming  off on several areas around the house, exposing the metal edge guards and allowing cold and moisture into the walls, as on the interior the skirting boards are cold and when furniture are places directly on the wall causing condensation and mould. ( as a short term solution, We have now left a minimum of 10 cm between the furniture and the walls, which seem to solve the problem of sweating skirting boards and mould).

 

Q1: Does anyone recognise what this exterior gab between the plinth and the wall is for?! is it just decorative or does it serve any purpose, like breathing of frame or expansion gab?

 

Q2: can this gab be closed and the house completely covered with an additional layer of acrylic render?

 

Q3: if the gab needs to be kept, how can we repair the damage? 

 

Any help and advice is greatly appreciated!

 

 

PS: As far as we can tell the house is built up of the following layers, starting on the inside: plasterboard, yellow insulation wool, OSB board, insulation board, acrylic render with embedded mesh and sits on a concrete foundation.

 

 

[ProDave]

No pictures? are you having trouble uploading them?  we need the pictures are your terms like "plinth" are not usual terms so we are guessing at the moment what the issue is.

 

But how old is the property? and where? 

[Naoma]

Sorry, I am having troubles getting my pictures uploaded.

 

It was built in 2003 and is located in county Westmeath, Ireland

[ProDave]

What happens when you try to upload them?  there is a size limit on attached files, if that is the issue can you reduce the size?

[Naoma]

I have tried uploading different sizes, still not working, maybe my internet connection is just not good enough today, 

I will have to leave it till tomorrow, when I am back in town and try there again

[Naoma]

Here are the pictures, sorry for the delay

[Naoma]

[markc]

Shabby!

what level is the ‘gap’ compared to the inside floor level?

the tape isn’t the problem here, it’s water getting inside through the perforated corner bead. Plus whatever is getting blown or pulled into the gap and then behind the upper render.

I think this really needs to come off from just above the joint line downwards and re applied.

can you see what is behind, especially the lower section?

[ProDave]

The upper part, the render, looks okay, terminated with a bell cast bead.

 

It's the lower part that is just wrong, I have never seen it done like that.

 

If it's done properly, the upper render will terminate at the same level as the damp proof course.  the lower part is then usually rendered with smooth render. No beads needed, it goes right up to the underside of the bell cast and is a thinner coat so it does not stuck out as far.

 

So I would be wanting that whole bottom section removed and re done properly without that silly gap.

 

You can see from rainwater downpipe, that this bottom render sticks out further than the bellcast of the main render which is totally wrong.

[Naoma]

The gab is on the same level as the inside floor.

 

We have been told that behind the grey render is concrete, and when you knock on it it doesn't sound hollow like the upper part where there is the insulation board under the render.

We have so far avoided to break any section, as the weather is still pretty bad and we don't want more cold/dampness to enter the house, but to be certain we might have to that then.

 

If I am understanding the feedback correctly, then there should be no reason to keep the gab and we could just get it closed off by redoing the grey section and making sure that it doesn't stick out.

Would it be ok to have it at the same level/ even with the upper section or does the upper section need to stand over the bottom part?

 

Thank so much

[Temp]

On many houses they only render the wall above the DPC. At the DPC there should be a bellcast to form a drip line (reminds me of flared trousers). The bell cast slopes out and down on the underside to prevent water tracking back in to the DPC. You can render below DPC but not all renders are approved for use below DPC.

 

The render below the DPC is normally thinner so that water dripping from the bell cast lands on the ground not the render below the DPC.  It looks like they added external wall insulation at some point and used too thick a layer below the DPC? You can see how the rainwater downpipe touches below the DPC but not above it. 

 

I think you need to see how far back the concrete is below DPC. See if it will be possible to re-render with a thinner layer so the bell cast works properly. Might be necessary to remove insulation below the DPC before rendering or at least protecting the top edge better? 

Edited March 15, 2022 by Temp

[Naoma]

If we knock back some area to see what is exactly behind the grey render and how far it goes back, is there anything we can do to protect the area temporarily, till we get someone to do the job?

 

In the case that we cannot knock it back far enough to get a correct connection with the bell cast, is there anything else we could do?

[Radian]

Am  I reading this wrong or is the problem that the frame is built on an un-insulated concrete slab?

[Iceverge]

Hi Naoma,

 

Welcome to the forum. Sorry to hear of your problem. It looks unfortunatly typical of celtic tiger lack of care and attention. However you are in the right place to get help.

 

Do you have any pictures of the interior skirting board, both where the render is damaged outside and where it isn't?

 

Can you privide a wider picture of the plinth detail too please?

 

Did an engineer survey the property an provide any guarentee for you?
 

 

 

 

 

 

[Naoma]

14 hours ago, Iceverge said:

Hi Naoma,

 

Welcome to the forum. Sorry to hear of your problem. It looks unfortunatly typical of celtic tiger lack of care and attention. However you are in the right place to get help.

 

Do you have any pictures of the interior skirting board, both where the render is damaged outside and where it isn't?

 

Can you privide a wider picture of the plinth detail too please?

 

Did an engineer survey the property an provide any guarentee for you?
 

 

 

 

 

 

Here are some more pictures, also showing how much the grey area stands out.

[Naoma]

There is no damage visible on the interior skirting boards, they just get wet when furniture are too close and eventually get mouldy, which so far we were able to clean off. 

 

Hope the above picture from outside is useful

[Temp]

I think the bell cast above the gap should have been much wider and the top of the grey plinth sloped down and out. Something like this..

 

Perhaps this wasn't possible for some reason. Can you tell if the DPC is at the top or bottom of the gap?  

 

[Radian]

On 15/03/2022 at 09:51, Naoma said:

The gab is on the same level as the inside floor.

 

 

6 hours ago, Naoma said:

There is no damage visible on the interior skirting boards, they just get wet when furniture are too close and eventually get mouldy, which so far we were able to clean off. 

 

To me, the wet sounds like condensation yet it seems everyone else is approaching this as if it were a leak. Condensation would be because the skirting is cold. The inside floor level seems to be the same as the concrete slab - i.e. not insulated. Therefore a cold floor. Can we establish whether or not the floor has insulation?

[Carrerahill]

On 15/03/2022 at 08:48, Naoma said:

Here are the pictures, sorry for the delay

Mess.

 

Not even sure what was supposed to be going on here, that will certainly cause you some water ingress issues!

[Naoma]

3 hours ago, Temp said:

I think the bell cast above the gap should have been much wider and the top of the grey plinth sloped down and out. Something like this..

 

Perhaps this wasn't possible for some reason. Can you tell if the DPC is at the top or bottom of the gap?  

 

 

I would say on the top, I will try to get some pictures from the area where the grey tape peels back the most, to give you as much info as I can

[Naoma]

This is the close up off the section with the grey tape pulled back

[Naoma]

This a picture of our front door, showing the floor level on the inside in relation to the gap on the outside, I hope this useful (sorry had to take the last two pic in the evening)

[Naoma]

2 hours ago, Radian said:

 

 

To me, the wet sounds like condensation yet it seems everyone else is approaching this as if it were a leak. Condensation would be because the skirting is cold. The inside floor level seems to be the same as the concrete slab - i.e. not insulated. Therefore a cold floor. Can we establish whether or not the floor has insulation?

As far as we have been told the concrete slab is insulated with some areoboard , I am not sure if there is any way to verify this now without causing too much damage.

 

Yes, there are no direct leaks to the inside (as in holes or water dripping/running), only condensation 

 

I have uploaded a pic of the floor level at the front door

[Naoma]

Would it be an option to close the gap off and create some kind of slope for the water to run down, as I looks like pulling the grey area back far enough to create an overhang might not be possible in many areas, as the grey part sticks out by sometimes nearly 1,5-2cm

 

 

[ProDave]

1 hour ago, Naoma said:

Would it be an option to close the gap off and create some kind of slope for the water to run down, as I looks like pulling the grey area back far enough to create an overhang might not be possible in many areas, as the grey part sticks out by sometimes nearly 1,5-2cm

 

 

I would want to strip some of the grey render off to understand firstly why it is so thick?  It is normally just 2 coats of sand / cement render and thinner than the roughcast coat.  and secondly to understand the logic of what they were trying to achieve with that gap?