This blog is dedicated to my good friend and concrete colleague Elaine Toogood. She recently inspired me to ‘get off my horse and write my blog.’ This came about through a discussion on sandpaper of all things.
"80 grit? 120 grit or indeed True Grit?" That was the question.
Of course we weren’t discussing the thespian talents of John Wayne or even listening to Glen Campbell... because the usual focus was on Visual Concrete of course. The subject in Elaine's holster was if sandpaper was a good idea to use for cleaning concrete surfaces…
We never got round to having that shoot out before, during or even after Eco Build. So in the spirit of sharing and, as John Wayne once said, “Tomorrow hopes we have learned something from yesterday.” here's what I think:
Ok, so if you want to find your True Grit for dry or wet cleaning concrete then Diamonds are a concrete’s best friend. Flexible Nickel encrusted Diamond hand...
On rare occasions we are asked to extend the dimensions of concrete either because the initial setting out was incorrect or because the piece just didn't fit into the space properly. Growing concrete is a great remedial work to undertake because it resolves big issues fairly simply. The repairs also look impressive which is a bonus.
The key to any good repair is respecting the plane of the existing material, getting a seamless flush finish and good texture match. Any hint of disparity here will drag the eye into disbelieving discourse with the brain and the repair will fail…. no matter how good the colour match is.
Columns, walls, window reveals can all be cultivated in this way. In this case precast treads were given the ‘gardening treatment’ to get a neat inserted finish into a stone lime washed wall. There were 17 treads in all with plenty of other post finishing to add to the mix. All good fun…
So what kind of blowholes are affecting our visual concrete? Big ones, medium ones and small ones? Yes those ones but there’s something else…
In our quest for an ever growing understanding of potential issues with visual concrete, like learning a language, the more you know the more there is to know.
We’ve come across another type of blowhole that we call ‘Milky Way Blowholes’… trillions of tiny minute pinpricks of air that make the concrete appear slight ‘browner’ in tone. In essence swathes of Milky Way Blowholes look fine, especially at 3m or so. There’s no point in touching them at all.
But what if within the galaxy of visual concrete these Milky Way Blowholes are punctuated by numerous ‘normal’ blowholes? A wormhole is opened and swallows you up for the following reasons:
Milky Way blowholes make the surface less dense with increased porosity. Whilst filling punctuated blowholes surrounded by dense concrete is not necessarily an issue, filling large blowholes surrounded by the Milk...
GreyMatter concrete is now 6 months old….To pat ourselves on the back and reflect upon this mini journey of Architectural Visual Concrete remedial work and consultation, here’s a list of projects we have undertaken and continue to undertake.
• Greenwich University School of Architecture
Architect: Heneghan Peng
Main Contractor: Osbourne
GreyMatter employed by Foundation Developments Ltd.
Fair faced concrete repair to insitu walls and columns.
• Watergate Farm
Architect: James Gorst
Main Contractor: Kingerlee
GreyMatter employed by Kingerlee.
Fair faced concrete repair to external wall and cantilevered soffit.
• Lancaster University Engineering building
Architect: John McAslan + Partners
Main Contractor: Eric Wright Construction Ltd.
GreyMatter employed by Eric Wright Construction Ltd.