I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.


--
Timothy Murphy
e-mail: gayleard /at/ eircom.net
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland

Timothy Murphy wrote:
I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.


A builder is not better than you, he's just done it before.

Timothy Murphy wrote:
I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.



Round here there are firms who come and fit loft ladders and hatches.
Last time I looked it really wasn't worth doing it yourself

Timothy Murphy coughed up some electrons that declared:


I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.



**** As always with free advice on USENET, please wait around for a bit to
see if there's are any refinements on what I'm about to write and make sure
no-one disagrees fundamentally with what's below. ****


Well - it sounds like a pretty standard loft-hatch arrangement.

I assume the joists are only holding the ceiling up? And are 4x2" or vaguely
thereabouts?

Personally (and I'm going by what I've seen, not done myself), I'd:

1) Prop the ceiling joist from below, the one that you're going to cut, at
both sides of the cut (unless one bit will be so short and near the
supporting wall that's it's obviously not worth bothering because you are
sure the ceiling will hold it - I'm talking a couple of feet or less long)

2) Cut the joist and remove the redundant bit in the middle.

3) Arrange two bits of 2x4" (or whatever the size of the joists are) across
the ends of the cuts like this (pieces ac and bd):


a b
=============================== uncut
| |
| |
==========|e f|=========== cut
| |
| |
=============================== uncut
c d

Fix new wood ac and bd at all points so that the joints can take vertical
loads. Often this was done by banging 4" nails into the side of one piece
through the end of the bit it was being fixed to.

This is how all the openings I've seen (not many) have been done.

*** I guess this is exactly what you were thinking of doing, based on your
description? ***

I'm not very keen on structural things (I like wet things and sparky things,
but not together!) and I would tackle a job like this, as long I was
absolutely sure that:

a) the joist wasn't doing anything else other than supporting the ceiling
(do you see any cross braces to purlins or anything like that?)

b) I'd propped it well - acro-props are dirt cheap to hire and you'd need
two, with a 4 offcuts of ply or plank to acts as pads top and bottom to
protect the floor and ceiling finish.

------

You might get away with cutting two joists for a decent sized hatch, but I
wouldn't want to commit to saying it's definitely OK it as I can't see your
ceiling.

HTH

Tim

Huge coughed up some electrons that declared:

On 2008-10-13, Tim S wrote:
Timothy Murphy coughed up some electrons that declared:


I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.



**** As always with free advice on USENET, please wait around for a bit
to see if there's are any refinements on what I'm about to write and make
sure no-one disagrees fundamentally with what's below. ****


Well - it sounds like a pretty standard loft-hatch arrangement.

I assume the joists are only holding the ceiling up?

Aren't joists normally under tension loads, because they're preventing the
eaves from being pushed outwards by the pitched roof?


That may be true. I'd assumed one could get away with the odd one or two
being cut as the affected roof rafters would be supported from spreading by
their neighbours (via the purlins and the numerous tile battens) and the
cut joists may pick up lenghtways support from their neighbours in similar
nefarious ways.

I'd be interested if there is a "proper" answer to this.

Cheers

Tim

Tim S wrote:
Timothy Murphy coughed up some electrons that declared:

b) I'd propped it well - acro-props are dirt cheap to hire and you'd need
two, with a 4 offcuts of ply or plank to acts as pads top and bottom to
protect the floor and ceiling finish.

I'd go along with TS's advice and disclaimers, other than to say that
depending on the size of the ceiling joists, it's quite likely that you
wouldn't need acrows; unless they are stonking great heavy joists I
would expect the plasterboard to hold them up while you're doing the
work. If you *were* concerened, you could poke your head up through the
new hole in the ceiling, screw down a perpendicular batten across the
top of the joist you're cutting and its two neighbours, which will take
the weight temporarily.

David

Huge wrote:
On 2008-10-13, Tim S wrote:
Timothy Murphy coughed up some electrons that declared:

I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.


**** As always with free advice on USENET, please wait around for a bit to
see if there's are any refinements on what I'm about to write and make sure
no-one disagrees fundamentally with what's below. ****


Well - it sounds like a pretty standard loft-hatch arrangement.

I assume the joists are only holding the ceiling up?

Aren't joists normally under tension loads, because they're preventing the eaves
from being pushed outwards by the pitched roof?

Mmm. In a truss, yes. with no load above the ceiling apart from end
pinned trusses.


But there are other ways to make a roof..warren bracing and purlins etc.

Purlins put them into compression, by and large, and a warren truss will
introduce bending moments. As will any loft load.

Tim S wrote:
Huge coughed up some electrons that declared:

On 2008-10-13, Tim S wrote:
Timothy Murphy coughed up some electrons that declared:

I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.


**** As always with free advice on USENET, please wait around for a bit
to see if there's are any refinements on what I'm about to write and make
sure no-one disagrees fundamentally with what's below. ****


Well - it sounds like a pretty standard loft-hatch arrangement.

I assume the joists are only holding the ceiling up?
Aren't joists normally under tension loads, because they're preventing the
eaves from being pushed outwards by the pitched roof?


That may be true. I'd assumed one could get away with the odd one or two
being cut as the affected roof rafters would be supported from spreading by
their neighbours (via the purlins and the numerous tile battens) and the
cut joists may pick up lenghtways support from their neighbours in similar
nefarious ways.

I'd be interested if there is a "proper" answer to this.


There is, but its entirely dependent on the exact roof layout.

But there is normally bags of redundancy, so go ahead and do it.



Cheers

Tim

"Timothy Murphy" wrote in message
...

I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.


--
Timothy Murphy
e-mail: gayleard /at/ eircom.net
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland

If you're going to do that brace the ends of the cut joist to the roof
suppoting beams metal ties, as when you climb into the loft space pressure
is put on the surrounding cutout loft hole because theres nothing to give it
support.

"Timothy Murphy" wrote in message
...

I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

Any advice or suggestions gratefully received.



I did a similar thing to get access to the roofspace over my garage. I first
chopped half into the one joist that was going to need to be cut, at the two
places where the cut piece was going to be removed from. I then took the two
pieces of wood (same X by Y size as the joists) and cut them the right
length to fit between the two adjacent joists, and similarly chopped in. The
cut pieces were then fitted in place, and end nailed to the adjacent joists.
The half-lap joint formed where the chop outs met, was glued and screwed,
and then the joist piece was sawn out. I finally made sure that it was all
strong and was not going to suffer sagging when a person's weight went on
it, by screwing down some ply around the opening, to form a platform to
stand on when you get up there. As others have said, I think that there is
enough redundancy in the roof construction for it not to be a problem, but
the way I did it at least ensured that there could not be any 'spread' when
the piece was cut out, as what was to become the cut ends, was already tied
to the adjacent joists

Arfa

On Oct 13, 4:13*pm, Lobster wrote:
Tim S wrote:
Timothy Murphy coughed up some electrons that declared:
b) I'd propped it well - acro-props are dirt cheap to hire and you'd need
two, with a 4 offcuts of ply or plank to acts as pads top and bottom to
protect the floor and ceiling finish.

I'd go along with TS's advice and disclaimers, other than to say that
depending on the size of the ceiling joists, it's quite likely that you
wouldn't need acrows; unless they are stonking great heavy joists I
would expect the plasterboard to hold them up while you're doing the
work. *If you *were* concerened, you could poke your head up through the
new hole in the ceiling, screw down a perpendicular batten across the
top of the joist you're cutting and its two neighbours, which will take
the weight temporarily.

David

That's what I'd do, no need for any props. The above temporary
crosspiece has the advantage that weight or force inadvertantly
applied to the unsupported PB wont bust a larger area of ceiling. Plus
its less wood use than a vertical timber prop - and at 2' you'd
probably find something from the scrap pile.

If the access were only very occasionally required, ie just to check
if repair is ever needed, I'd consider not bothering with the joist
operation. A foot is hardly generous but it is enterable/exitable.


NT

I wouldn't make the hole square...
it can be longerlong the direction of the joists,
making it easier to get in ind out...

and, as someone suggested,
can you squeeze between the existing joists?

I dont know if i can get through a foot wide...

depends on how high the roofspace above where you put the hole is,
I guess the more height above it the better,
and a rope hanging down to help pull yourself up...

[g]

The Natural Philosopher wrote:

I want to make a hole in a plasterboard ceiling
to get access to the roof-space in my one-storey cottage.
I have found that the joists are 1 foot apart,
and am thinking of making the hole a little under 2 feet square,
which would mean cutting one joist.
and putting 2 cross-pieces to hold the joist.

Is this a job I can do myself? Or should I get a builder.
I'm reasonably handy.

A builder is not better than you, he's just done it before.

Thanks to all for the generous advice.
I think I will take the coward's way out,
and leave the job to a builder.

Incidentally, the reason for the project
is that a professional insulation expert
refused to get up through the present access hole,
which is admittedly very awkward to climb through.
The roof space is just 50cm high.
The expert said that he employs several Polish men
who will install insulation for him almost anywhere,
but that this was too much even for them.


--
Timothy Murphy
e-mail: gayleard /at/ eircom.net
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland

On Oct 13, 9:40*pm, "George \(dicegeorge\)"
wrote:
I wouldn't make the hole square...
it can be longerlong the direction of the joists,
making it easier to get in ind out...

and, as someone suggested,
can you squeeze between the existing joists?

I dont know if i can get through a foot wide...

depends on how high the roofspace above where you put the hole is,
I guess the more height above it the better,
and a rope hanging down to help pull yourself up...

[g]

IMLE its a good deal easier to climb into narrow gaps like that from
atop a flat surface than from a ladder. So you dont need the ladder
either.


NT

On Oct 13, 9:40*pm, "George \(dicegeorge\)"
wrote:
I wouldn't make the hole square...
it can be longerlong the direction of the joists,
making it easier to get in ind out...

and, as someone suggested,
can you squeeze between the existing joists?

I dont know if i can get through a foot wide...

depends on how high the roofspace above where you put the hole is,
I guess the more height above it the better,
and a rope hanging down to help pull yourself up...

[g]

IMLE its a good deal easier to climb into narrow gaps like that from
atop a flat surface than from a ladder. So you dont need the ladder
either.


NT

.... and narrow entrances are easier if a decent width in the other
direction due to body movement.


NT