Review

Adjustment of drain, and connection of new channel

We are in the midst of laying a new patio, and are at the stage where the base is being laid out. Before continuing, we need to get the drainage sorted (or at least, not get in the way of getting the drainage sorted). As we've lowered the level of the patio as compared to what was previously on the ground, one of the drains (marked Drain 1 in the attached images) is now too high, and adding insult to injury, we're not sure it's even draining properly... This drain needs to be altered so that the top sits lower to the ground, and a connection needs to be made to the drainage channel and a drain to be installed in the "cupboard" area shown in the images. The drainage channel may also need to be connected to the other drain (Drain 2 in the images)? We already have some (though probably not quite all not all) of the materials: the channel, the small drain for the cupboard, 2 90 degree elbows, a 45 degree junction, and a couple of sections of 90mm pipe, but we do not have the expertise to alter the drain or make the new connections ourselves. Please see images for a clearer idea of the nature of the job. A site visit, if required, would be welcome.