Dotting the i's and crossing the t's should see the deal finanlised tomorrow.
"It'll be paperwork first thing Monday morning, that's the only thing holding that one up," Malky Mackay said.
"I'm glad to get that one in, he's someone we've tracked for a year and he's had a successful year for Brentford.
"He's one that I think is a real prospect. For the future of the club, I've got three really good goalkeepers now; Simon comes in and I think he can kick on again.
"My thanks to Brentford for the way they went about their business, they were very professional and it was done very quickly."
Steve Borley tweeted on Friday that he'd signed the contract on nehalf of the club so it should just be a formality.
Moore, who played 52 games for Brentford last season, will compete with Joe Lewis and current No.1 David Marshall.
Simon Moore highlights