Saturday, 17 September 2011
Insulation part 1
We want to get the house insulated and energy-sorted. Im discovering its not easy and straightforward to retrofit an 1860s victorian terrace.
There are a number of different projects that need tackling.
This is one - sorting out an area at the back of the house - its a cold corner, I think for several reasons - the solid wall is an external one - the neighbours' room stops short of our probably edwardian extension, there isn't a radiator really adjacent, and there is a very nice Velux window, which lets in a lot of light during daylight hours and is double glazed, but i bet there is some heat loss through it.
There has been damp coming through - I think from a bush that was growing ito the brickwork, but the wall has been stripped for a while and seems to be dry now.
Part of the wall has a cupboard along it , so its a relatively small area that is exposed. Ceiling to floor is approx 290 cm and the length of wall is approx 190cm. We thought studs and sheeps wool and then plasterboard is overkill. So its a board of some sort. And I've read that damp can be a problem, as any moisture condenses on the cold surface of the wall . So the joins in the board etc are taped. But what about at the top and the bottom ? Does it mean that it will only really work well if its fully insulated and sealed at the top and the bottom to prevent ingress of water vapour laden air - Ive therefore got to remove the skirting board, and the original moulding ( it may eventually all be going - but that doesn't solve *this* problem.). The room isn't used a lot at the moment - so it shouldn't be a problem ( should it ? )
Ive gone to google ( as you do ) . Heres a forum discussion that includes stuff about calculating the dew point of a wall. if I can calculate the dew point, I could show that it may not be a problem and another forum that highlights the problem of excessive condensation and it having nowhere to go
Ive not yet found the 2007 iso standard but there is this powerpoint about condensation (surface and interstitial) . its got 2 pictures - this of internal insulation (which hasn't got vapour barrier)
and this of a timber-framed wall ( it looks like a stud with insulation between, and plasterboard on top ) - but this has got a vapour barrier .
I think what I need is the Glaser method of calculating the dewpoint.
Some of the insulation boards that you can buy come with an integral vapour barrier. But will end up not letting moisture out ?
or are we back to thinking about studs and lambswool as the insulation , because that will breathe , or what i have seen listed as 10mm flexible liner - it looks like its 'polystyrene wallpaper'
Labels:
drylining,
greening,
insulation,
internal insulation
Friday, 9 September 2011
Javascript Associative Arrays
I've spent some time looking into Javascript associative arrays. But javascript doesn't have associative arrays. it has objects that can have values that can be accessed in a similar way to associative arrays in perl and PHP. Im no expert but heres how I created a multidimensional javascript array from a PHP array .
The PHP array has 4 levels , that are read from a database .
So I've read data from the database and created a multidimensional PHP associative array
$ic[$sy][$si][$pr][$co]=$value;
so the php writes some javascript
The PHP array has 4 levels , that are read from a database .
So I've read data from the database and created a multidimensional PHP associative array
$ic[$sy][$si][$pr][$co]=$value;
so the php writes some javascript
Thursday, 1 September 2011
backing up - or not.
ive got a good system running for backing up windows machines .
I thought Id sort out the backing up of my linux machine as well.
So i thought id do the same thing
I thought Id sort out the backing up of my linux machine as well.
So i thought id do the same thing
- create a shared folder on the remote system
- make it accessible to the computer I want to back up .
- run rsnapshot and Im done
on the server root@server:/home/backup/mars/hourly.0/mars# ls -la /home/backup/ | grep ma drwxrwxrwx 4 mars users 4096 2011-09-01 14:27 mar root@server:/home/backup/mars/hourly.0/mars# on the client mar@mar-desktop:/mnt$ mount | grep nfs 192.168.2.20:/home/backup/mar on /mnt/marbackup type nfs (rw,vers=4,addr=192.168.2.20,clientaddr=192.168.2.3)
and i get this mars@mars-desktop:/mnt$ sudo rsnapshot -c /etc/rsnapshot.conf hourly require Lchown Lchown module loaded successfully Setting locale to POSIX "C" echo 6806 > /var/run/rsnapshot.pid mkdir -m 0755 -p /mnt/marsbackup/hourly.0/ /usr/bin/rsync -avx --delete --numeric-ids --relative --delete-excluded \ --temp-dir=/tmp --exclude=*iso --exclude=Dropbox/* --exclude=Ubuntu* \ --exclude=.* --exclude=Downloads/* /home/mars \ /mnt/marsbackup/hourly.0/mars/ sending incremental file list created directory /mnt/marbackup/hourly.0/mars /home/ rsync: chown "/mnt/marbackup/hourly.0/mar/home" failed: Remote I/O error (121) /home/mars/ rsync: chown "/mnt/marbackup/hourly.0/mar/home/mars" failed: Remote I/O error (121) /home/mars/A4L Flyer (2up, 2x A5).ott /home/mars/Agenda_Committee Net Meeting_17_July_2011.pdf /home/mars/CTX.DAT etc on the server its this root@server:/home/backup/mar/hourly.0/mars/home/mar# ls -la total 1956 drwx------ 21 nobody nogroup 4096 2011-09-01 14:38 . drwx------ 3 nobody nogroup 4096 2011-06-04 15:27 .. -rw------- 1 nobody nogroup 113146 2011-08-26 13:40 a4flyer.jpg -rw------- 1 nobody nogroup 9955 2011-08-26 12:16 A4L Flyer (2up, 2x A5).ott -rw------- 1 nobody nogroup 71243 2011-07-17 20:10 Agenda_Committee Net Meeting_17_July_2011.pdf I can access the backed up stuff from the server , as root . but when i come to run the backup again it fails mars@mars-desktop:/mnt$ sudo rsnapshot -c /etc/rsnapshot.conf hourly require Lchown Lchown module loaded successfully Setting locale to POSIX "C" echo 6918 > /var/run/rsnapshot.pid native_cp_al("/mnt/marbackup/hourly.0", "/mnt/marbackup/hourly.1") mkdir("/mnt/marbackup/hourly.1", 0755) safe_chown(4294967294, 4294967294, "/mnt/marbackup/hourly.1") ---------------------------------------------------------------------------- rsnapshot encountered an error! The program was invoked with these options: /usr/bin/rsnapshot -c /etc/rsnapshot.conf hourly ---------------------------------------------------------------------------- ERROR: Warning! Could not safe_chown(4294967294, 4294967294, "/mnt/marbackup/hourly.1"); ERROR: Error! cp_al("/mnt/marbackup/hourly.0/", "/mnt/marbackup/hourly.1/") /usr/bin/logger -i -p user.err -t rsnapshot /usr/bin/rsnapshot -c \ /etc/rsnapshot.conf hourly: ERROR: Error! \ cp_al("/mnt/marbackup/hourly.0/", "/mnt/marbackup/hourly.1/") rm -f /var/run/rsnapshot.pid mars@mars-desktop:/mnt$
the problem is the root_squash option in nfs . The defautl is root_squash - ie stuff transferred across is owned by nobody, rather thatn user that can do stuff.
So i changed the mount options to
rw,no_root_squash, and added the same user (mar) to the server .
But still not fixed.I think the UIDs have to be the same as well
And the ssh option in rsnapshot looks like its a pull backup option rather than push.
Hmmm . I'l have to have think about this
Subscribe to:
Posts (Atom)