Repairing Bay Window Columns

[bpk101]

Does anyone know what these decorative concrete (plaster?) columns are called either side of the main bay windows found on Victorian terraced properties:

I’m renovating my house and would like to repair, re-render and decorate all concrete areas around the windows including the window-sills and these decorative columns which are in very poor condition.

My builder has recommended we replace the columns rather than try to repair them as the decorative detail has already been greatly lost due to past repairs by previous owners.

Any idea what they’re called or where I might head for traditional looking replacements?

Thanks

 

[bobby spray]

I would try and keep them if at all possible. Modern replacements will likely be of inferior quality.... if you can get them. I would be surprised if the window cills are cement. more likely to be either natural stone or lime based stucco. These are more than 100 years old. Some degradation adds to the character. .... Sounds like your builder wants the easy way out!

BS

 

[bpk101]

Thanks BS -

So how do we best go about repairing them? A lot of the terraced houses in our neighbourhood have had similar repair work done to the bay window masonry and they all look fantastic:

I have knocked on a few doors but annoyingly all occupants bought the properties post-renovation so couldn't shed any light on how the repairs were carried out.

How can i get my stonework...

Looking as clean and sharp as some of the neighbouring renovations?

 

[bobby spray]

First you need to gently strip off that paint right back to the substrate. Then use a lime based repair mortar such as Lithomex
http://www.masonsmortar.co.uk/knowledge/page/lithomex
to fill in the missing chunks. it takes a small amount of skill to do this and it can be used to recreate lost decorative features.
Lithomex is what we use up here but I'm sure that there will be something similar available in your area.
use a breathable paint on the stonework when finished. Gloss will eventually flake and look awful

the important thing is to never ever ever use concrete on a building like this.

good luck

BS

 

[bpk101]

Thanks BS - that's really helpful.

Is my builder safe to use concrete for the new hard standing area in front of the window bay and footpath leading to front door (which we will later tile)?

Have to say i'm getting a little nervous our builder isn't that experienced with older properties.

Would these breathable lime based products need to be used for internal plastering of walls and ceilings too?

 

[bobby spray]

if he's going to put a hardstand around your house make sure he digs out what is already there first. If you raise the ground level you'll have a chance of damp internal walls. So you want the finished surface including tiles no higher than it is at the moment.

Modern plaster is ok for the interior.

BS

 

[bpk101]

Yes the idea is to actually dig out the current hardstand and put the new one in slightly lower so it's below (150mm?) the DPC... if indeed there even is a DPC in an 1880 house?!

My concern is the foundations in that front bay are very shallow and our pre-purchase structural did note slight historical movement in that bay area.

Will digging out the current hardstand and installing new air bricks be cause for concern if our builder isn't well versed in victorian properties?

 

[ree]

Excellent advice above.

Never replace historic detail such as the columns. Its bad enough that someone down the line replaced the Box double hung wood frames with PVC, probably removed a Victorian tiled path, and concreted over a strip of garden. They will have also, to save a few measly bob, demolished the original garden wall and built whatever crude thing you now have.

Its doubtful that the render above the plinth is original - that was probably applied as a remedial measure. As above, the bay & render appears to have been plastic painted - likewise the exemplary pic of the bay down the road.

You will need a min of three 10" x 6" air bricks in the front elevation. Check the condition of the floor joists sitting in that bay and the underfloor thro ventilation from front to rear.

After cracking out the concrete hardstand try to keep the bottom of the plinth from ground contact - chop it back if necessary. Be alert that your utilities might have been run just below the concrete - dont assume correct depth.

An 1880 house might have a DPC (Blg Regs from 1875) and a faint cavity but dont count on it. Dont allow any injected DPC nonsense.

The style of the columns is a Victorian composite of various styles but very typical for its time.

 

[bpk101]

Modern plaster is ok for the interior.

BS

Definitely? According to this site:

http://www.rics.org/uk/news/news-insight/comment/top-10-crimes-against-period-houses/

The top 10 inappropriate works commonly carried out on traditional buildings

2. re-plastering or rendering main walls with cement-based materials rather than traditional lime, thereby trapping damp in the walls.

Should i be checking our builder is using lime based render?

 

[bobby spray]

Some good points in that link and sage advice in the comments. I believe that re re rendering refers to external walls. if you have damp penetrating into the house it doesn't matter what type of plaster you have, the finish will suffer