Jump to content

Search the Community

Showing results for tags 'concrete cracking'.

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • BuildHub Guide: Information about the site : Introduce Yourself
    • About BuildHub.org.uk
    • Introduce Yourself
  • Build Design, Planning, Finance and Legal
    • Building Plots, Land & Renovation Properties
    • Design & Architecture
    • Funding, Finance & Tax
    • Insurance, Legal and Warranties
  • House Construction & Structural Issues
    • House Construction
    • Conversions & Extensions
    • Roofing & Lofts
    • Structural Works, Foundations & Demolition
    • Insulation & Ventilation
    • Landscaping & Outdoor Buildings
    • Damp & Infestation
  • Building Trades
    • Plumbing & Heating
    • Bricklaying, Plastering, Concrete, Blocks & Rendering
    • Joinery, Windows & Doors
    • Floors & Flooring
    • Electrics, Lighting & Home Security
    • Decorating & Tiling
    • Kitchens & Bathrooms
    • Building Materials
  • Environmental, Alternative & Green Building Methods
    • Designing Energy Efficient & Sustainable Homes
    • Renewable Home Energy Generation
    • Research & Information Sources
    • Environmental Building Politics
    • Boffin's Corner
  • Self Build & DIY: General
    • General Self Build & DIY Discussion
    • Housing Politics
    • Property TV Programmes
    • Tools & Equipment
  • Self Build Regional Groups
    • UK
    • Europe

Blogs

  • Salamander Cottage
  • The House At Mill Orchard
  • An Orkney Build (in ICF)
  • The House at the Bottom of the Garden
  • Hawthorn House
  • Rose Lane re-build
  • East Kent Self Build
  • Wee Hoose on the Croft
  • God is in the Details
  • Tennentslager
  • Kentish RenoExtension
  • Scooby Cottage renovation.
  • The Seasalter Sharp House
  • sussexlogs
  • Sips and stones may break my bones...
  • Our Journey North of the Border
  • Construction in Cornwall
  • The Fun Irish (House)
  • A house! A house! My kingdom for a house!
  • South Devon Self Build
  • Lucy Murray
  • Coffee Towers
  • caliwag
  • caliwag
  • Blackmore House
  • A woodland house
  • Druim nan Darach
  • Escarpment to the countryside
  • Recoveringbuilder
  • Netherwood lakes
  • Kingseat
  • Mr and Mrs Triassics New Home
  • Yaffles
  • Wedding Cake Re-build
  • Clancutt Lodge
  • Self-Build in Shropshire
  • South coast ICF build
  • 5 (2 adults, 3 dogs) go building in Dorset
  • Hillcroft
  • Self Build NE Scotland
  • Timber Portal Frame - but stick built
  • Self Building two in North Wiltshire
  • 1970s Chalet-style house renovation
  • Under the Chestnut Tree
  • The Larch House
  • Building in a woodland on the Isle of Wight
  • Back on the self-build waggon...
  • Gardening in the Lockdown
  • The BuildHub Gardening Blog
  • West Sussex Forever Home
  • Testing
  • Canalside Bungalow Renovation
  • Holywood Passive ICF Build
  • Finchampstead Passivhaus
  • Albaston self-build
  • Little Stud Barn
  • South East Cornwall Low Energy build
  • Scottish SIPS build
  • Gus Potter
  • Garden Escape
  • error
  • ASHP, MVHR, PV and EV combo
  • The Windy Roost
  • Wind! Yes I know but....
  • Big Bungalow Build!
  • A Rainfuel project
  • Making a cheap electrical energy meter
  • Rainwater Harvesting
  • Lessons from the road...
  • Dragons in the North
  • Surrey self build
  • The Old Cow Shed
  • Major extension and eco renovation in Leicestershire
  • Canski
  • Canski
  • Deep refurb and extension
  • Bog Lane Former Water Works
  • Renovation of Ellesmere Bungalow.
  • Energy
  • Hampshire self-build. Cheap, high quality and fast - we want all three
  • Da Bungalow
  • Air tightness - The cost of everything and the value of nothing.
  • Contemporary Dream

Find results in...

Find results that contain...


Date Created

  • Start

    End


Last Updated

  • Start

    End


Filter by number of...

Joined

  • Start

    End


Group


About Me


Location

Found 1 result

  1. A word about concrete slabs, especially in hot weather. Concrete is a highly sophisticated product, and with proper handling it produces effectively rock to the shape you want. Many things can go wrong, but they can all be controlled. The principle is that we are gluing together bits of rock, back into the form we want, using cement. There should always be a proven formula for the mix. For a bridge or multi-storey it is very much more precise and controlled than for a garden path, but it is always worth attention. The main thing that most public don't realise is the difference between cement and concrete. Cement is ONLY the dust that goes in the mix to make mortar or concrete. The biggest important thing that many in construction do not know is that concrete is strong through curing, not drying. Do not assume that your groundworker knows all, or much, of this. For a strong concrete mix there are large stones, with all the gaps between filled with small stones, and the further gaps filled with sand. Every surface is coated with the slurry of cement and water that has been carefully mixed in. There are no pockets of cement, it is all aggregate to aggregate contact. A chemical reaction then happens that makes the cement stick everything together, and water is used in this reaction, and taken out of the mix as a permanent part of the matrix chemistry.. Any additional water will simply sit in the mix, until it evaporates, leaving lighter concrete and miniscule gaps. It is essential that there is the right amount of water. a) enough to allow the chemistry to occur. b) not too much that it spoils the mix and eventually leaves voids in it. The chemistry takes many days, and concrete gets harder for at least a month, if properly looked after. For this to happen, the laid concrete must not be allowed to dry out, so it must be covered with plastic or wet hessian. Once the surface is hard, water can be sprayed over it. Don't use too much water, and don't allow the concrete to dry out through sun or wind. If it is very hot or windy, postpone it. (Frost is another matter). Why do supposedly expert groundworkers have problems with cracking? Mostly because they add extra water, by hand or by asking the delivery driver*. This makes it much easier for them to handle. Secondly because they don't know the difference between drying and curing, and want it to go hard so they can go home. Thirdly incorrect use of steel mesh (which is for cracking control not strength), dpm, and joint preparation. (* A readymix company will allow water to be added, but will record this on the delivery chit, and thus it is not their problem. They may also takes samples and make cubes for testing, and store them in a tank of water for ultimate strength, for 7 and 28 days.) All concrete cracks. How and how much it cracks is the skill. Enough for now, do ask for clarification or more information.
×
×
  • Create New...