Hollow Core

Ted10

Ordering the hollow core for a new build in the next few weeks. Does anyone have any advice whether it's better to get holes pre drilled for services or wait until the plumber decides where he wants them and drill them after it's been laid. Also is there much involved in grouting the hollow core, most of the companies don't seem to grout it or charge it as an extra. Is it possible to do as a DIY job ?

Thanks

De_man

personally, i'd have a chat with the plumber and sparks about this, it's near impossible to accurately core for bathroom fittings etc at this stage...
water inlets etc all vary according to the type of bathroom/shower suites you order

when it comes to coring don't bother getting someone into do the job...
depending on services etc, it could cost you up to 1500 to do all the cores..
i'd hire a coring machine incl bits - cost per day 153inc vat. i did some of the cores myself but looking back now i'm sorry i didn't do all of them

regarding the grouting of the joints it's a small job, but very important and will only take a few hours to do. (3:1 mix if fine)

Sonnenblumen

Makita do a very good diamond core set with a vg drill and approx 6-7 cores for around € 400.00+VAT

Cheiftan

I'd also speak to your flooring manufacturer prior to coring as there may be restrictions as to where you can actually core , if you core through one of your re-inforcing strands it would be a bad move.

Mellor

I imagined the drilled cores are drilled into the precast cores. So drilling through the prestressing strands shouldn't be an issue as they are between the cores afaik

De_man

"Sonnenblumen" Makita do a very good diamond core set with a vg drill and approx 6-7 cores for around € 400.00+VAT

Pity i'd didn't see that whilst doing my job:( it sounds perfect for the job

Ted10 precast is the way to go imho, but think about as to how you're going to do the ceilings underneath!!!
a lot of people (as discussed earlier in previous threads between myself and salmon et al) had various solutions to this problem. my blockwork was perfect but saying that the slabs in the hall were difficult to work with. i had to use a Z hanger due hall design

you can cross batten the ceilings with express nails 2 X1.5" battons
(my method and i wouldn't do it again)

put up a metal "lattice" with laser

or what i should have done put up 4 X 2s at the sides of the walls (taking into account pipe runs etc, with laser level, then use hangers and batton out with 4 X 2s (suspended ceiling) this imho whilst the most expensive option would have been the easiest in the long run

this also give you enough room and a ground for putting up cornice etc

i must stress i'm not a builder but i've just been through this
if you're in trouble PM

lfcjfc

De Man,

Can I ask why you wouldnt do yours the same way again?

De_man

i found that i had to use "spacers" to ensure that the cross battens were level with each other, a very time consuming job in a couple of areas most notably the hall and one part of the kitchen (where the design was complicated), the other rooms were perfect.

the hassle of drilling underneath the precast floor to insert the express nails was a complete nightmare of a job - i just wouldn't do that again..

4X2s on hangers is the way to go imho