Minimum working temps

[Tony McC]

I uploaded a new FAQ a couple of weeks back, dealing with what work can and can't be done when it's too cold or too hot.

On the topic of blacktop, I'd originally written that work usually continued down to 0°C but not over frozen sub-bases.

Yesterday, I was having a bite of lunch with a senior manager from one of the bigger block paver manufacturers and he told me he'd previously worked for a very large, multi-national blacktop company, and the rule was work was stopped if the temp dropped below 5°C.

I've wasted an evening looking through the documentation for blacktop surfacing and I can't find a reference to this 5°C, only to 'frozen sub-layers'.

What's the experience of other blacktop gangs?

[Dave_L]

3 degrees and rising is the general rule.

We've been very lucky this winter so far.

Thawing out the subase with large gas torches, laying base at 50+mm is fine, only gets inadvisable to carry out thin surface overlays at low temperatures.

[GB_Groundworks]

waiting on it to warm up for 125m2 drive, incidentally our neighbors had their drive done last 2 days its been 4 or 5 in days but is -5 now the sun as gone down

[dig dug dan]

whilst on the subject, during a;ll that snow and the big freeze, i was at a supplier of Indian stone picking up literature, and a landscaper came in who was actually laying slabs in the snow.
I asked about pointing and he said he was mixing it with frost proofer, and it wasn't a problem.
Is this correct? what happens to the sharp sand and cement he has laid on in the cold?

[lutonlagerlout]

I think he has booked a ticket for the failboat dan
a lot of my mates have had 8-9 days out on big sites due to temperature, 4 deg and rising for BWK
we laid 400 blocks tues-wed and it was close to it maybe 6 degrees tops,then covered with hessian and celotex
LLL

[msh paving]

.
I asked about pointing and he said he was mixing it with frost proofer, and it wasn't a problem.
Is this correct? what happens to the sharp sand and cement he has laid on in the cold?

I'm prety shure frostprofer is used to protect outside render once its set not while wet,there fore its not a bit off use in wet pointing and will fail.......MSH

[dig dug dan]

that's what i thought. I managed to point some paving on Saturday with easipoint. they told me it's ok 4 degrees and rising. it was a sweltering 8 degress!

[Tony McC]

Frostproofers are generally just an accelerator. They speed-up initial hydration but I've never, ever trusted them for anything critical.

[Dave_L]

Lads were out planing out and patching the local highway today in zero to +1 conditions with snow about, crazy or what???

SCC Highways must be taking the "Just get it done" approach.

[michaelthegardener]

they were patching the main road here to dunno what the temp was but there was snow on everything else !

[seanandruby]

We did a 900 metre raft slab pour yesterday, started at 7.00am and the boys where still there at 9.00 pm. had to be powerfloated because of a 100ml screed top up at a later date .it was freezing and then the snow came. A bit of cold won't stop the programme ( got to be open 2018 ). I left at 4.00 to beat the weather traffic wise, had to come off on the dorking a24 for deisal and it took 7 / 12 hours to d0 50 miles. A24 by Capel was just a sheet of ice.

[lutonlagerlout]

we worked recently in temperatures approaching or hovering around zero, I have a feeling there must be minimum temperatures for men to work in,especially for a big outfit such as yours sean?
I gave the lads 2 days money drink for working through it but it would annihilate us financially to pay them for the next 2-3 weeks if it stays like this
this whole weather situation just adds insult to injury with the economy the way it is
LLL

[seanandruby]

If the site is covered in snow, then it becomes a risk. We have designated walkways and those are treated chemically and the ice broken up. We were sent home two weeks ago because of severe weather. It also depends on workload ie; a mass pour of concrete that took nearly a week to get ready is going to get done , no matter what. We cover the intended pour the night before to keep rebar free from ice, as we pour we have a three pronged burner to heat the steel and melt the ice as we go. The concrete has additives to keep it from freezing. Straight after powerfloating everything is covered in a frost blanket for a few days. I was sat in a cage covered in ice, erecting pipework the other week -6, could'nt feel the little nuts on the collars, hands where that cold. plus my arse was frozen, things you do for a few bob :laugh:

[mickavalon]

We've just been trying to snag out our first Swimming Pool, just got the make good of the surrounding and a few odds and sods, trouble is we can't even see the ground let alone do anything with it. Spent most of Friday Fecking about with the ladder/steps and the surface skimmer. Pools not heated and boy was the water cold. I had no feeling in me hands for a good 20 mins after pulling Pebbles out the Skimmer Basket and they were only in the water for 5 mins.
Made the mistake a few Winers ago of trying to finsh some slate Paving in -3, re-laid the whole 30m2 in the Spring...never again

[Tony McC]

I've had a caller today checking the veracity of his contractor's claim that it's OK to lay flags on top of the snow, as it will just melt away and all will be just grand.

The contractor has now offered to scrape away the snow!! :O