Blown pebble dashing

[thetcutkid]

Hi all,

I wonder if I could get some opinions on the best way to tackle the following (sorry for the long post btw)...

1930's semi, block paved drive slightly inclined towards house, morons who laid it donkey's year's ago laid it above the height of the damp course so inevitably we had damp problems with the lower front bay. We got someone in to take a look and they pointed out the issue with blocks being higher than the damp course and lowered the blocks nearer the house to below the damp course.

However, there is no drainage channel incorporated in the drive so the water runs down towards the house, around the bay and into the drain...I do try and keep the area free of weeds and muck etc but any obstacle around the bay makes the water pool and we now have very severe damp problems on the inside of the bay with the floor starting to part company with the bottom of the skirting board.

This week I've noticed some major cracks in the pebbledashing around the bay and in one area it's completely blown and actually raised off the bricks beneath (there are additional issues with 8 massive conifers our neighbour uses as a hedge line which they refuse to trim) and we have had two nights of very heavy driving rain on the front of the house.

I appreciate that there are several problems here and really, the water running down the drive needs to be solved before we do anything else, however, due to me being a full time carer for my father I'm initially looking for a quick fix on the pebble dishing.

If it was July, I'd be tempted to remove the pebble dashing around the whole bay and just let the bricks dry out for a few weeks, however, as it's nearby December and the weather has been awful, I'm thinking about just removing the blown area and resealing with some quick drying cement (I don't care how it looks, I just want it weatherproof for the winter)

1) I take it that its poor practise to cement over already damp brickwork ?

2) Come next year when hopefully we can have it done properly, will the builders curse me as they try and get quick drying cement off the bricks ?

Is there another option for patching - silicone sealant into the cracks for example ?

Many thanks for your time and apologises once again for the long post.

Nick

 

[vinn]

Why not post pics of inside and outside the bay, show ground level, and the whole bay against the house elevation?

 

[thetcutkid]

 

[thetcutkid]

The main area of blown pebble dashing is more or less in the centre of the bay, with cracks running down and out from it, with separate cracks left and right.

Regarding curing the water problem, in the small amount of research I've done, I've never seen curved drainage channels (the type with the channel and metal grill) however I have found guttering companies that will extrude curved aluminium guttering to basically any radius you like, so I was wondering whether the single row of bricks touching the bay could be removed and a guttering channel put in around the bay and into the drain.

 

[vinn]

There's no quick or temporary fix - if you attempt any one thing it will lead into something else.
Plus there's the problem of the trees - see the Council ref such trees, they can be a contributing factor to your difficulties esp. concernig drains, foundations & hard surfaces, if not now then in future.

The best practice is for the dash and plinth render to come off back to bare brick.
Time of the year is irrelevant for most building work.
A linear drain is a possibility but where will it drain to - a mains, a soakaway?
There's a down pipe RH of the bay, so perhaps it could discharge into wherever the RWP drainage goes?

Removing the dash on the lower face of the bay, and then chasing out, repointing & applying new render & dash will work - treating the cheeks of the bay esp. the LH side would be difficult but not impossible. All render should break ground contact about 50mm from the ground level.

It would pay to remove bricks to examine the cavity for debris bridging the DPC?
You also need more 10" x 6" air bricks to be sure of ventilation - the porch is blocking the LH air bricks.
Do you have CWI?

Inside the bay remove all plaster and skirting back to brick.
Lift some floor boards and examine the joist tails sitting in pockets in the inner brickwork. If you have sub-area space to crawl then examine all the joisting along the front wall.
Also determine if you have sufficient through ventilation or if moisture is condensing below the floor?
The floor has dropped which usually indicates rotted joists.

 

[thetcutkid]

Hi vinn,

Many thanks for your detailed reply, its much appreciated.

You'll have to excuse my ignorance but what is CWI ?

Regarding the trees, we were in touch with the council a few years back and whilst on the phone, they went onto google earth and were horrified at how big they were. However, they say they are a last resort with regards to resolving the issue and want £500 (non refundable) to take on the case.

Yes, on the right hand side of the house is a rainwater downpipe into a proper drain (not soakaway) so in my mind I envisage a drainage channel feeding into this.

As I'm not really in a position to have all the work done now, would just taking all the external render off back to brickwork be of any use in helping the bricks to breathe and dry out or will it just make matters a hundred times worse with winter weather on old, damp bricks ?

 

[vinn]

For temporary "repairs" simply fill all cracks with a polysulphide sealant gun cartridge.
If chunks are hanging off then pull them off and rough patch up with sand and cement.
If it all more or less seems to be blown then just knock it all off to brick and leave it until you are ready.

If the bricks are sodden and/or the cavity is blocked then it wont "dry out" but it wont get worse after removing the render.

There are no cheap or easy solutions.

 

[thetcutkid]

Hi vinn,

Totally appreciate it won't be cheap (or easy) to do the job properly but I need a bit of a stop gap as it were - I appreciate this doesn't necessarily sit well with the Pro's as, quite understandably, you want to advise on doing the job correctly, however I do appreciate your input and advice.