After six minutes Ross Wallace's right-wing corner was saved at the near post by Reading's Australian goalkeeper Adam Federici.
Neill Collins' shot a minute later and an inswinging Wallace right-wing corner after eight minutes were saved.
Preston captain and goalkeeper Andy Lonergan used his feet to save a low close-range shot from Jobi McAnuff after ten minutes, after he had beaten Billy Jones on the left wing.
Lonergan saved after 20 minutes when Brian Howard's low corner skidded along the wet turf towards the near post and Simon Church got a touch on it.
Chris Sedgwick's header was tipped over from Wallace's free-kick after 25 minutes but it was ruled offside.
Church raced away from Richard Chaplow and hit a 15-yard shot under Lonergan into the bottom right-hand corner to make it 1-0 to Reading after 34 minutes.
Jem Karacan found Jimmy Kebe and he beat Eddie Nolan and fired low into the net from 15 yards after 43 minutes to make it 2-0.
Darren Carter replaced Chaplow at half-time.
Chris Brown had a header cleared off the line by Ivar Ingimarsson two minutes into the second half and then had a left foot 'goal' ruled offside after 50 minutes.
McAnuff had shots saved after 54, 58 and 59 minutes and Sedgwick's crosses were saved.
Jon Parkin replaced Sedgwick and Matt Mills replaced McAnuff after 67 minutes.
Wallace's 25-yard shot was tipped onto the bar after 68 minutes. Neil Mellor's shot was saved after 75 minutes and then he hit the post.
Wallace hit the post after 77 minutes. Kalifa Cisse replaced Karacan after 78 minutes. Mills fouled Parkin and was booked after 80 minutes.
Parkin sent Federici the wrong way and made it 2-1 with a penalty into the bottom right after he had been fouled by Mills after 84 minutes.
Jones and Cisse had shots saved after 85 minutes.
Grzegorz Rasiak and Youl Mawene replaced Church and Liam Chilvers after 87 minutes.
Brian Howard, and Kebe were booked for fouls after 89 minutes. In stoppage time Collins, Mellor and Parkin had shots saved.