Installation
Tips #2
REPLACING THE SINK INTO NEW WORKTOPS, ON NEW
OR EXISTING BASE UNITS
Unfortunately
most installation tips we have read over the years
appear to have been written by persons who probably
have never fitted a sink in their life. We have
given a few tips below based on over twenty five
years experience of supply and professional installation
in the kitchen industry.
Prior
to fitting sink and worktops, make sure your base
units are level, not only from left to right but
also from back to front, it is very difficult to
adjust base units once worktops have been laid on.
It is a good idea to leave out the back and the front
top rails of the sink base (we will give reasons
for this later)
When you have fitted the worktops and cut the joints (where needed) leave the
joints dry, do not glue them yet. In the worktop that will house the sink,
use just one or two screws to secure it in position whilst the sink aperture
is cut, try to place the screws away from the cutting area for obvious reasons.
When marking out the position of the sink, take into account the general position
of the bowls in relation to the sink base unit and washing machines or dishwashers
that may be adjacent.
Some sinks come with a cutout template which we would recommend using, we would
however advise you check the template size against the recommended cutout size,
as templates can vary in their accuracy.
It is
certainly advisable to use a template on irregular
shaped sinks, although a more regular rectangular
shape sink should not pose a problem without a template,
provided you follow our advice.
DO NOT, despite advice given
elsewhere, turn the sink upside down, place it on the worktop,
draw around it and then draw inside by 10mm, the reasons are
as follows 1 - you can have too many lines drawn which may
be confusing, 2 - every time you handle the sink you run the
risk of damaging the machined edges which give the clean lines
when fitted, 3 - you may scratch the worktop especially if
using High gloss worktops. Only use this method as a last resort.
Leave the sink in the box until you need it.
ASSUMING YOUR USING A RECTANGULAR SINK
If you know approximately where you will be positioning the sink it is a good
idea to place masking tape along the line of the cut, this will serve two purposes,
1 - on dark worktops you will be able to see the pencil line and 2 - it will
help protect the worktop surface from the baseplate of your jigsaw.
Always work from the positioning of the bowls making sure the bowls will sit
within the width of the sink base unit. If using a 600mm deep worktop you may
want to position the sink to the centre of the depth I.E.. 300mm from the back
edge to the centre of the sink depth, (always measure from the square edge
of the back of the worktop rather than guess from the bull nose of the front).
If the overall size of the sink from back to front is 500mm the cut-out will
usually be 20mm less (check against manufacturers recommendations) this means
the cut-out depth (back to front) is 480mm, so from the centre mark on the
worktop measure back 240mm and forward 240mm, the line at the back will be
60mm in from the back edge of the worktop, you can then make several marks
along the length of the proposed cut and use a straight edge to join the lines
up, you can also make a mark towards the front of the top at 540mm from the
back edge of the worktop, making several marks along the length and joining
them up. If you have nothing to use as a straight edge, borrow a shelf out
of a 1000mm wall or base unit, you will now have two parallel lines at 480mm
apart. If the overall length of the sink is 1000mm the cut-out will usually
be 20mm less (check against manufacturers recommendations) this means the overall
cut-out length will be 980mm. Make a centre line in the length of the top,
making sure you have positioned the bowls correctly, Measure 490mm either side
of the centre line and draw a 90°square line, if you don't have a square
use the borrowed 1000mm base or wall unit shelf again. You should now have
a pencilled rectangle with square corners. Depending on the radius of the corners
of the sink you will need to cut at least 15mm radius corners (not in to the
corner).
Before actually cutting out the aperture for the sink, remember the old saying
used in the Building Industry "measure three times and cut once",
you certainly wouldn't be the first to cut the aperture wrong.
Contrary to some advice we have read, we have found the sink aperture is best
cut when the worktop position has been decided and the worktops are fixed in
place, all be it on a temporary basis. It is not advisable to make the cut-out
for the sink whilst the worktop is supported on saw stools, although your worktop
supplier will be more than happy to supply you with more worktops after you
have picked yours up and snapped them.
It's a good idea to use just one or two screws to hold the worktop in position
whilst cutting; these can be removed if you need to move the worktop slightly
to get the jigsaw along the back cut.
With regards to leaving the sink base top rails out till later, the reasons
for this are, sometimes the front cut in the worktop comes very close to the
front of the carcase top rail and this can snap when cutting the worktop, plus
you are cutting through another thickness. Cut the top rail down in width after
the sink has been fitted and then offer up and fix to the worktop. The back
rail could be fixed in the vertical position and screwed or glued to the wall.
CUTTING THE WORKTOP
This is the part that most Diy enthusiasts hate, they have
just spent lots of money on new worktops and are now about to cut away a
large proportion of them.
Providing you have marked out correctly and checked your measurements against
the manufacturers recommended cut-out sizes you can't go wrong.
Start
by drilling a minimum 15mm hole (check with manufacturers
recommendations) in each corner keeping within
the lines. Using a jigsaw with a new sharp blade
cut along the length and depth of the cut-out connecting
the holes. On the last segment make sure you support
the piece of worktop that is to be removed as this
may well fall and damage the base unit.
When you're happy that the cut-out is as neat as you can get it, try the sink
in on a dry run (no sealant). The sink should be sitting flat on to the worktop
all the way round, if the sink is slightly bowed, push down gently to see if
it will seat down when the clips are applied later. If the sink is unable to
seat properly due to the cut-out not being big enough, then remove more of
the material and try the sink again until you are confident it will seat down
perfectly.
Remove the sink now and place safely out of the way. The raw edge of the cut-out
must be sealed at this stage, we would advise a PVA type water based waterproof
glue for this purpose. In order to allow the glue to absorb into the chipboard
core, water down the first coat and liberally coat around the cut-out, allow
this coat to dry and then coat with a neat coat of PVA. Make sure the cut-out
is completely sealed, giving another coat if necessary.
GLUEING WORKTOP JOINTS
If fitting on a Diy basis or even if you're having professionally
fitted, on no account should worktop butt & scribe joints be sealed with
silicone. Silicone will not adhere to the chipboard core of the worktop and
will allow water to ingress and in time the worktop around the joint will expand,
the only remedy being complete replacement of worktops. A waterproof glue should
be used or one of the specially produced worktop adhesive/fillers available
in various colours from your worktop supplier.
Now is a good time to permanently fasten down the worktops.
FIXING THE SINK
After fixing all of the worktops you can permanently fix down
the sink. Sinks are usually provided with fixing clips suitable for worktops
of between 28mm and 42mm. In the case of worktops outside this thickness range,
the underside of the worktop should be either rebated or thickened with blocks
of wood or similar.
It is easier to fix the tap on to the sink before putting it into the worktop
also the wastes and overflow can be fixed to the sink at this stage. When preparing
the sink, check that all the clips are in place, and that the under edge is
free from dust or grease.
Apply a good bead of clear silicone sealant to the worktop at this stage in
a continuous run around the top edge.
Next gently lower the sink into the aperture and ensure that you can see silicone
being squeezed out as the sink is pushed down. If there is a gap where no silicone
has been squeezed out then carefully ease up the sink and insert some more
sealant in to fill the gap.
We
can not stress too much, how important the sealing
down of the sink is, if you are to avoid costly
repairs later on. Some sinks come with a foam or
similar seal attached to the underside of the sink,
this would probably be sufficient to seal the sink,
but as a belt and braces approach we would still
advise to use silicone. Next lightly tighten the
fixing clips, but do not over tighten and make
sure you follow the manufacturers instructions
as to the procedure.
If for some reason you find your sink has no clips with it but you want to
complete the installation, don't be alarmed, providing the sink is sitting
down well all the way round the aperture, the silicone will not only seal the
sink but will also hold it in place. You would be advised though to put some
weights on top of the sink until the silicone has cured, possibly overnight.
REMOVING THE SURPLUS SILICONE FROM
AROUND THE NEW SINK
We have found if you use a blunt knife around the edge of
the sink to make a cut between the sink and the surplus silicone and then
wait approximately half an hour, you will be able to pull off the surplus
in one piece. A word of warning though - if you leave it too long you will
be picking and rubbing at the silicone for hours. Don't be tempted to use
a scraper to remove the silicone you risk taking the surface off the worktop.
COMMISSIONING THE NEW TAP
Having connected the tap and turned on the water it is essential
to flush through the tap in order to flush out any solder that may have
been left in the pipework also any rust or particles of grit or large particles
of limescale that may have been disturbed when altering the pipework. Failure
to flush the system through properly could result in the new tap being
damaged.
MANUFACTURERS WARRANTY
Remember that damage caused by improper handling or installation
of your sink or tap will not be covered by the Manufacturers warranty.
DISCLAIMER
All advice given in the previous paragraphs is on a totally
independent basis and not necessarily the recommendations of the manufacturers
of your sink or tap.
We cannot be held responsible for any problems that may arise resulting from
the use of this advice. |
