I bought a 8 year old house with strip oak engineered flooring. In one of the rooms a small area had water damage. The person who repaired(I use that term loosely) the floor, cut out about 8 damaged peices and plugged with a not even close match (slightly thicker and narrower). The exisiting hardwood does not appear to be made any more.

Now i would like to replace the flooring in the room as it looks like crap now. I have osb subfloor that appears to be 5/8", the engineered is glued to it. Joists are 24" on center. What is the best way for me to put down a new floor. Is it to cut out the hardwood and subfloor in 1 shot and put down a new subfloor. This is a 1st floor room , crawl space house.

If I cut out the subfoor,I will use a sawzaw to cut as flush as i can to the walls. How then do i support the edges of the subfloor flush at the walls. The joists are engineered 2x10's 24 on center so not sure how to put a nailer between them.

Is there any easier ways to lay down new engineered hardwood in this scenario???/

Since you are over a crawl space, you could lay another floor on top of your existing floor, as long as it's flat and securely installed. I would install a 6 to 8 mil polyethylene vapor retarder under the house in the crawl space as well. You could nail, glue or float another floor over your existing, assuming the new height would not interfere with doors, cabinets and appliances. A 5/16" T&G solid could be ideal for this. Tearing out the subfloor will be a pain but it can be done. You may need to scrape or sand off adhesive from the tops of your trusses. To support the ends at the walls, you just sister on new 2 x material (2 x 6 ) to the rim joist. If you are not knowledgeable in framing and carpentry, it may be a good idea to hire someone for this part. It needs to be done right.