Take a section of guttering and mount it on a bracket.
Position it against one end of the fascia board as close to the roof tiles as possible.
Using a pencil or marker, mark the top of the bracket.
Using a nail, attach a piece of string, long enough to reach the opposite end of the fascia.
Move to the other end of the fascia and tighten the string, use a spirit level to ensure it is positioned horizontally. Secure the end of the string with a nail.
Repeat this process for all the fascias.
Using a plumb line, mark positions on the fascia which are vertically above the rainwater drainage points on the ground. These are the points at which the gutter will be lowest.
The gradient of the gutter will need to be at least 1:600 (i.e. for every 3m of guttering, a 5mm fall is needed).
If there is one outlet at the end of the fascia, calculate the fall needed for the length and adjust the string as required at the outlet end.
If there are outlets at each end of the facia, add an additional nail, to hold the string, in the middle of the facia. After calculating the necessary fall for each side, from the middle of the facia to the end; lower each end of the string accordingly.
If the outlet is part of the way along a fascia, lower the string at this point, calculating the fall using the longer length of facia, attach a nail to support the string.
You have now purchased your seamless gutters, downspouts and fittings. Removed your old system (if you haven't removed it refer to article How To Remove Old Gutters and Downspouts). Prepared your guides, gathered your tools and you are now ready to start fitting your new system.
Ensure ladders are placed on a level surface and secured. All fittings should be secured using rustproof screws.
Fitting the first outlet
Attach the outlet to the fascia using the string as a guide.
Next, attach a bracket 100mm in from the end or corner, allowing space for the last fitting.
Attach further gutter brackets at regular intervals, not more than 1 metre apart, make sure they are not fitted at any join points.
Fitting the gutters
Beginning at the outlet, place the first length of gutter on the brackets. Position it so that the end is about 5mm from the stop end inside the outlet.
Manoeuvre the back edge of the gutter under the clips at the back of the brackets. Carefully pull the front edge down into the front clips.
Attach a jointing piece at the end and continue along the facia. Make sure you always allow 5mm clearance from the gutter stop within the fittings; this is to allow for expansion.
Your last length of gutter will need to be cut to fit. This is easy to do with a hacksaw. Sand or file off any rough edges. This length will either fit into a corner piece or a stop end. If using a stop end, allow the gutter to extend past the end of the fascia by about 40mm.
Fitting the downpipes
At each outlet, attach an offset bend pointing towards the wall. Position a second offset bend slightly off the wall ensuring it will line up with the downpipe which will be fitted using brackets.
Measure and cut a length of pipe so as to connect the two offset bends.
Holding a length of downpipe onto the bottom offset, place a pipe bracket over it to secure.
Using chalk or a pencil, mark the screw positions for attaching the brackets to the wall; drill and plug the wall.
Fit the bracket and secure the first section of pipe.
Repeat the process at 2m intervals adding new sections of downpipe if necessary.
At the drainage point, the pipe will need to be cut to size, use a hacksaw and sand or file, as before.
If the downpipe is to be fitted into an underground drainage point, ensure it is long enough to fit into the drainage housing.
If the downpipe feeds into an open drain, cut it 50mm above the drain, and attach an outlet shoe.
Repeat the process for each of the outlets.
You have now installed your new system! To ensure optimum drainage, regularly clear gutters and outlets of leaves and debris.