Does it make sense to cast plinths? Consumption dry concrete

[holyanna]

I am planning to build a pergola and have downloaded the forest industry's PDF on how to do it. They recommend either driving the post 60 cm into the ground and filling it up with concrete or buying ready-made plinths.

From what I find, it takes about 4 bags of dry concrete per post! Can that be right? Seems insanely much (almost 100 kilos). A bag seems to cost 80 kronor, which becomes 320 kronor per post.

Wouldn't it be much cheaper to buy plinths? And simpler? Or have I got it all wrong?

 

[anaitis]

Concrete mix 39.95/bag at Byggmax
http://www.byggmax.com/se-sv/Prod/PID-0103.aspx

Usually, 2 bags per pole should be enough, but it depends on the ground and how you dig. For example, you can also press in "extra" stones when casting.

 

[holyanna]

Thank you for the answer! Is this grovbetong the kind that needs to be mixed in a cement mixer or large bucket? I think it seems so convenient with the kind you pour directly into the hole and water.

 

[anaitis]

Mix in some form of plastic container. A LARGE bucket might work. Often available for a cheap price. I have personally used the wheelbarrow sometimes, but clean it immediately otherwise it will stick.

 

[sponken]

If you come down with the plintar, it is much smoother (and cheaper) than casting yourself. If it is a pergola, plintar will almost certainly suffice. Make sure you take plintar with two flat irons and not those with a beam shoe on a "pin."

/sponken

 

[holyanna]

Aha, so you mostly cast yourself when it comes to really large constructions? It's starting to become clear, I'm not particularly knowledgeable about this (dimensioning etc.). Thanks for the model tip, I know which one you mean. I'll remember that.

 

[jerk]

A finished pier including an adjustable beam shoe costs around 130 kr at Bauhaus and you won't need to mix. If you buy two bags + paper tube and beam shoe, it will probably cost about the same. Dig out, throw in a little gravel in the bottom and place a garden slab about 30x30. Then you have a good surface to place the pier on and a larger area to distribute the load.

 

[holyanna]

Thank you for the tip! We have lots of old garden tiles we don't know what to do with

 

[BAS]

If you drill the hole, you get a stable concrete pillar.
If you dig and place a pre-made plint or drive down a pipe, you get concrete constructions that wobble back and forth.
A drilled plint doesn't need as much concrete.

 

[holyanna]

Thank you BAS. At first, I was like a question mark, but now I've ordered a skurupsborr. This is going to be exciting!