The first step to installing a shower pan and drain is to remove the old drain pipe and start preparing the subfloor. Firstly, position your shower pan in the space where you want your shower and mark that position. Then use a jigsaw to start cutting a hole in the subfloor around the mark where you want your shower pan placed. You can either cut one or two holes in the subfloor. However, the hole has to be good enough to reach into a PVC saw to cut the old drain pipe. Remember to always use safety equipment like safety glasses when working with power tools.The next step is to complete the subfloor preparation and start installing the pan. You may need to add a sheet of plywood to the subfloor to ensure the shower pan is level with the rest of the bathroom. All you need to do for this is cut a piece of plywood that fits the space and then secure it with a caulking gun and screws. Then set the shower pan in the position you wanted and mark the location of the drain hole. Drill the hole marked so you can fit the new drain. The final step is to assemble the new drain and fit it appropriately. Cut the PVC pipe to the appropriate length and then dry-fit the PVC fittings. Once the components fit properly you can apply PVC cleaner to the components being joined. Following that, use PVC cement and slip the PVC into place. Hold the pieces in position for a short period of time as you wait for the cement mix and PVC cleaner to react together. Then attach the new drain cover. You have now successfully installed a shower pan and drain.If you need any further help with plumbing, heating, appliances or installations, hire Plumbers Walthamstow who are your number one choice for fast and reliable plumbing services. Plumbers Walthamstow has a team of experience plumbers who can be sent to your property at any time of the day because of our 24 hour availability.