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[email protected] June 22nd 07 10:17 AM

Cavity wall construction
 
Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.


John June 22nd 07 10:42 AM

Cavity wall construction
 
On 22 Jun, 10:17, wrote:
Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.


This should be specified by your archtect. 8" sounds about right.
It will certainly be checked by building control during the
construction.

John


TMC June 22nd 07 01:01 PM

Cavity wall construction
 

wrote in message
ups.com...
Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.



The first step is to commission an architect to draw up the plans.
(They do not have to be done by an architect but need to contain a full
construction specification so it is often an architect who does them)

He will visit the site to measure up and discuss with you what you want

The plans will contain all information regarding footings construction
materials insulation roof structure etc. He would also commission a
structural engineer should one be needed

These plans are then submitted to the local council building department for
approval.

The architect will normally know if the plans will also require planning
permission

Once the plans have been passed you would then use them to get quotes from
builders based on those plans or from individual tradesman for each aspect
of the work

When I last did this I also ordered all materials and contracted in such
labour as I needed so essentially I acted as the builder would have done

As project manager you will then supervise the builder/tradesmen to see that
they follow the plans and do the work to the standard you require
you would notify the building control dept as required to inspect each stage

I know other people who have started the process by asking a builder for a
price based on talking with them and then the builder arranged for the plans
to be drawn and submitted and then carried out the work

Tony






Rob June 22nd 07 01:23 PM

Cavity wall construction
 
TMC wrote:
wrote in message
ups.com...
Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.



The first step is to commission an architect to draw up the plans.
(They do not have to be done by an architect but need to contain a full
construction specification so it is often an architect who does them)

He will visit the site to measure up and discuss with you what you want

The plans will contain all information regarding footings construction
materials insulation roof structure etc. He would also commission a
structural engineer should one be needed

These plans are then submitted to the local council building department for
approval.

The architect will normally know if the plans will also require planning
permission

Once the plans have been passed you would then use them to get quotes from
builders based on those plans or from individual tradesman for each aspect
of the work

When I last did this I also ordered all materials and contracted in such
labour as I needed so essentially I acted as the builder would have done

As project manager you will then supervise the builder/tradesmen to see that
they follow the plans and do the work to the standard you require
you would notify the building control dept as required to inspect each stage

I know other people who have started the process by asking a builder for a
price based on talking with them and then the builder arranged for the plans
to be drawn and submitted and then carried out the work

Tony


Out of interest, how much did the architect charge? I've been quoted 10%
of the project cost by a RIBA architect - but it's a bit chicken/egg - I
need the plans to cost the project.

Thanks, Rob

TMC June 22nd 07 01:41 PM

Cavity wall construction
 

"Rob" wrote in message
...
TMC wrote:
wrote in message
ups.com...
Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.



The first step is to commission an architect to draw up the plans.
(They do not have to be done by an architect but need to contain a full
construction specification so it is often an architect who does them)

He will visit the site to measure up and discuss with you what you want

The plans will contain all information regarding footings construction
materials insulation roof structure etc. He would also commission a
structural engineer should one be needed

These plans are then submitted to the local council building department
for approval.

The architect will normally know if the plans will also require planning
permission

Once the plans have been passed you would then use them to get quotes
from builders based on those plans or from individual tradesman for each
aspect of the work

When I last did this I also ordered all materials and contracted in such
labour as I needed so essentially I acted as the builder would have done

As project manager you will then supervise the builder/tradesmen to see
that they follow the plans and do the work to the standard you require
you would notify the building control dept as required to inspect each
stage

I know other people who have started the process by asking a builder for
a price based on talking with them and then the builder arranged for the
plans to be drawn and submitted and then carried out the work

Tony


Out of interest, how much did the architect charge? I've been quoted 10%
of the project cost by a RIBA architect - but it's a bit chicken/egg - I
need the plans to cost the project.

Thanks, Rob


Hi rob

Was a few years ago & I can't remember the fee

Unfortunately he died suddenly (in his 40's) a couple of years after
otherwise I would have asked him for you

Tony




Roger Mills June 22nd 07 01:56 PM

Cavity wall construction
 
In an earlier contribution to this discussion,
wrote:

Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.


How are you going about getting Building Regs approval for your extension?
Assuming you're in England or Wales (Scotland may be different) there are
two different approaches which you can adopt. The more usual one is to draw
up (or pay someone else to draw up) detailed plans which contain the full
technical details of how the building will be constructed - and get them
approved *before* getting quotes from tradesmen for the actual work. These
will contain details of the cavity wall construction, floor construction and
insulation, roof construcion, door and window specs, etc. - and leave little
room for argument.

The alternative approach is to do it on a Building Notice - where you submit
much less detailed plans and then negotiate each detail with the Building
Inspector as the work progresses. This gives you more flexibility to
'refine' the design but also makes it much harder to get fixed price quotes
from tradesmen because the BCO might insist that they do something they
weren't expecting, thus adding to the cost.

It's a good idea - especially if you're doing your own plans - to go to have
a chat with a BCO at your local council and find out exactly what they'll be
looking for before you start. If it's obvious from your approach that you
want to do it right, but are not quite sure what to do, I have always found
them to be very helpful and supportive. They'd rather help you get it right
first time than get into a dispute when they come to inspect something which
*hasn't* been done right.

If you're doing your own project management, this book
http://www.whsmith.co.uk/whs/go.asp?...220&Menu=Books is a
"must read". Looks like WHS are doing a good deal on it, or you'll probably
find a copy in your local library.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!



TMC June 22nd 07 02:21 PM

Cavity wall construction
 

"Roger Mills" wrote in message
...
In an earlier contribution to this discussion,
wrote:

Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?

Any advice/help will be greatly appericated.


How are you going about getting Building Regs approval for your extension?
Assuming you're in England or Wales (Scotland may be different) there are
two different approaches which you can adopt. The more usual one is to
draw up (or pay someone else to draw up) detailed plans which contain the
full technical details of how the building will be constructed - and get
them approved *before* getting quotes from tradesmen for the actual work.
These will contain details of the cavity wall construction, floor
construction and insulation, roof construcion, door and window specs,
etc. - and leave little room for argument.

The alternative approach is to do it on a Building Notice - where you
submit much less detailed plans and then negotiate each detail with the
Building Inspector as the work progresses. This gives you more flexibility
to 'refine' the design but also makes it much harder to get fixed price
quotes from tradesmen because the BCO might insist that they do something
they weren't expecting, thus adding to the cost.

It's a good idea - especially if you're doing your own plans - to go to
have a chat with a BCO at your local council and find out exactly what
they'll be looking for before you start. If it's obvious from your
approach that you want to do it right, but are not quite sure what to do,
I have always found them to be very helpful and supportive. They'd rather
help you get it right first time than get into a dispute when they come to
inspect something which *hasn't* been done right.

If you're doing your own project management, this book
http://www.whsmith.co.uk/whs/go.asp?...220&Menu=Books is a
"must read". Looks like WHS are doing a good deal on it, or you'll
probably find a copy in your local library.
--
Cheers,
Roger



Yes it is worth speaking with BCO and if others nearby have had extensions
built recently you may be able to get some good info about the nature of the
ground and likely footing depth issues, routes for foul water and storm
drainage pipes that may affect the groundworks as many people have had
unforeseen expenses once the digging started. However if your architect is
local he may have good knowledge anyway

There are lots of cautionary tales to be told about building work e.g.

My next door neighbour has last month applied for a single storey
garage/store attached to the side of his house as has been told by BCO (not
Planning) that he cannot simply put in a concrete raft for this but must put
in proper footings in case in the future there is an application to add an
upper floor (the difference in cost is 4 extra skips for the waste say £600
and £1200 extra for the concrete and then the extra time and labour which
has doubled the cost of the project)

Tony



[email protected] June 22nd 07 04:49 PM

Cavity wall construction
 
I was thinking about going the lawful development route and I have
been speaking to the planning dept about this. I live in London in the
borough of Barnet. My Ext is going to be around 18m2 (6x3) with a flat
roof at the back of my house, my neighbours has the same ext already.
Currently the space is occupied by a conservatory which will get
removed.


dennis@home June 22nd 07 07:48 PM

Cavity wall construction
 

wrote in message
ups.com...
Does anybody know where I could possible get hold of cavity wall
specs ? basically I'm looking at managing a extension project myself
but I want to be sure that everything is done right and according to
BC. Some of the builders I have had in for a quote tell me that for
the floor be it solid or wooden, they have to dig about 8" down and
then build it up with a mixture of hardcore, insulation and DPM, is
this correct ?


Only eight inches?..
mine was dug down by about 6 feet and a concrete raft laid with more steel
in it than a motorway bridge..
then the floor was laid about 2-3 feet thick with more steel in it.
If it ever sinks I should be able to put a cable under each corner and lift
the damn thing if I can hire a big crane.

Totally ott as the house next door has 3 foot deep strip foundations and
there aren't any mines or anything like that here.




Hugo Nebula June 23rd 07 10:40 AM

Cavity wall construction
 
On Fri, 22 Jun 2007 13:56:34 +0100, a particular chimpanzee, "Roger
Mills" randomly hit the keyboard and
produced:

It's a good idea - especially if you're doing your own plans - to go to have
a chat with a BCO at your local council and find out exactly what they'll be
looking for before you start. If it's obvious from your approach that you
want to do it right, but are not quite sure what to do, I have always found
them to be very helpful and supportive. They'd rather help you get it right
first time than get into a dispute when they come to inspect something which
*hasn't* been done right.


With the caveat that the BCO won't design it for you, and will get
very ****ed off very quickly if you start asking him to.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

Roger Mills June 23rd 07 03:55 PM

Cavity wall construction
 
In an earlier contribution to this discussion,
Hugo Nebula abuse@localhost wrote:

On Fri, 22 Jun 2007 13:56:34 +0100, a particular chimpanzee, "Roger
Mills" randomly hit the keyboard and
produced:

It's a good idea - especially if you're doing your own plans - to go
to have a chat with a BCO at your local council and find out exactly
what they'll be looking for before you start. If it's obvious from
your approach that you want to do it right, but are not quite sure
what to do, I have always found them to be very helpful and
supportive. They'd rather help you get it right first time than get
into a dispute when they come to inspect something which *hasn't*
been done right.


With the caveat that the BCO won't design it for you, and will get
very ****ed off very quickly if you start asking him to.


I didn't suggest that he would. But hopefully he will tell you what U value
you need to achieve, and where to find tables of material properties that
you will need when working out how to achieve it, and things like that. When
I did my extension on a Building Notice, I bounced my plans informally off a
BCO and got some very useful pointers on bits which I needed to modify. I
don't know whether all councils are the same, but my council always has one
'duty' BCO in the office whom you can drop in and see if you need advice.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!



Hugo Nebula June 24th 07 11:42 AM

Cavity wall construction
 
On Sat, 23 Jun 2007 15:55:37 +0100, a particular chimpanzee, "Roger
Mills" randomly hit the keyboard and
produced:

In an earlier contribution to this discussion,
Hugo Nebula abuse@localhost wrote:


With the caveat that the BCO won't design it for you, and will get
very ****ed off very quickly if you start asking him to.


I didn't suggest that he would. But hopefully he will tell you what U value
you need to achieve, and where to find tables of material properties that
you will need when working out how to achieve it, and things like that.


No problem with that, but it's the owners who ask, "what size rafters
do I need?", "how much insulation do I need in the walls, roof and
floor?", "what's a damp-proof membrane?". I've some single storey
extensions in progress that I've spent more hours on than I have on
whole housing estates or multi-storey office blocks. The owner saves
£500 on a set of plans, everyone else who puts plans in has to cover
the £500 of extra work it takes to sort out their mess.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"


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