Hi Dan I have had a look around and could not come up with a answer to your question. However because the floor has such a huge slope into the drain this is what I suggest.
You have to run string lines from the back to the front and from side to side over the waste area. Then you have to extend the waste up just a little under the strings where they cross . You then have to knock out the waste grill and extend your new extension down into the old waste. You can buy wastes with removable grills in them this is the type we have in our new shower. I do not know what the waste pipes are made from but you could extend up by using plastic or what ever you use over there. Now you have to fill around the area to bring the floor up to a level which your string lines show. You could use crushed rock leaving about three inches to fill with cement so cutting the cost of cement but around the waste slope it a little down towards the waste so it has a small falls if water can drain out. If you want to keep the head height as is you could then paint the floor with a water proofing agent oar rubber based paint. It is difficult to suggest a solution not being able to run my hands over the area but ask your brother in laws what would they do to rectify this problem the more suggestions the better. The bottom line is the waste has to be extended up and then the floor filled in. Regards Ray ********************************************************************** This message and its attachments may contain legally privileged or confidential information. If you are not the intended recipient, you must not disclose or use the information contained in it. If you have received this e-mail in error, please notify the sender immediately by return e-mail and delete the e-mail. Any content of this message and its attachments which does not relate to the official business of Eraring Energy must be taken not to have been sent or endorsed by Eraring Energy. No warranty is made that the e-mail or attachment(s) are free from computer virus or other defect. ********************************************************************** [Non-text portions of this message have been removed]
