hi guys im a first time caller! i dnt know if i have a problem or not. i have to tell you my exact set up to let you get the best idea.
my floor is on the ground floor of my house. the ground floor of my house is a concrete slab.
this is the method i used
dpm first
battens at 300mm centrse [2x2]
polystyrene between battens
battens sheeted with 6mm ply
18mm oak flooring ranging from 300mm to 1200mm lengths 90mm wide porta nailed down with 38mm nails
there is a 12mm gap rite round the floor
STUPIDLY!!!!!!!!! i wood glued down the last row at either end of the room. i done this because i could not get the nailer in and wasnt thinking at the time. i thought this would be the best way because i didnt want to nail through the face i realize now that maybe the floor can not move.
so here is my problem the floor has been down for around ten months it gets cold in my house at nite then we wake up and put the heating on . i find thet my floor is creaking in places not bad but i notice it cause i laid it!!!!
is this the start of somthing bad or is this normall it never creacked before it is only me and my girlfreind.

your help and advice would be greatly appreciated regards andy

First off your ply thickness should be 5/8 inch min. And then your shocking your floor by turning the heat on and off. It should be kept at a constant temp within the 60 to 85 degree range is preferable.

Gluing the ends is ok, not a problem there if you used flexable urethane adhesive.

hi stephen ! thanks for the reply .
i didnt think the thicknes of the ply would matter as i was nailing to the batten the ply was only to make laying easier{does ply thickness matter?} as for the glue stupidly i used normall wood glue!{will this matter?} as for the temprature to keep the heating on constantly would cost me a fortune ! { is this really bad?}
is creaking normal or have i got problems?
look forward to hearing from you
regards andy

Plywood thickness does matter for support and proper fastener grab.
The nailing schedule should be every 8 inches & 4 inches from the ends. So if you only nailed to the "battens" ( every 2' ), your short quite a few fasteners.

Creaking is normal with expansion and contraction of solid wood floors. But you may experience a little more than usual, due to the lack of fasteners and temp swings.

thanks for the reply howard !
should my battens have been in at 4-8 inch centres ? this seems quite alot !

The every 8 inches and 4 inches from the ends is how often the hardwood floor should be nailed to the minimum 5/8 plywood.

It's not that bad though, I doubt it is going to blow off the floor. just think of it as a old world floor.

I guess it's kinda like a floated naildown

whats an old world floor ?

"old world floor" in this case I imagine refers to creaky bones, lol.
Did you nail through the 6 m.m. plywood anywhere where a fastener may have intruded into the polystyrene? If so, that will be an instant squeak due to the flexing of the floor system between the battens.

Whats a batten??

In this case, its the 2 X 2's used at 300 mm as a base for the 6 mm plywood, and to allow for fastening of the 3/4 inch hardwood.

to me the creaking is coming from the joins in the wood at cerain places ! how long can a floor be down before you would notice if there is a problem?

Dennis,

So am I to understand that you nailed 2x2's to the concrete slab, then 6mm plywood to that, then nailed down the wood planks into the plywood? Sorry for the Metric Conversion here but 6mm is less than a 1/4". That seams a little thin to me even though you spaced the studs roughly a foot apart.

Application methods tend to differ regionally but I will agree with some earlier posts that 1/4 plywood is not stiff enough. I would probably choose 5/8"CDX or roughly 16mm plywood. The thicker plywood will allow the staples or nails to hold on a little better.

I've never thought of nailing down a 2x2 to the slab and floating a floor on top of it. Down here in Texas, building methods for the cold weather are definitely different. We use a specialty nail gun and nail the 5/8" ply directly to the concrete slab. I like the idea of doing that if a client wants a more well-insulated floor or the flexible feel of a pier and beam floor under foot.

If I were you, I'd be on the lookout for potential issues related to excessive flexing. You might prevent a total loss if you dismantle the finished floor and reinstall it with thicker plywood as a subfloor. An additional layer of your 6mm would probably add a sufficient amount of rigidity. Be on the lookout for cracking along the groove side of the planks. Pay special attention to the areas of the floor that have really heavy furniture on them. Hopefully you'll dodge a bullet. At a 12" spacing between your studs, you may be okay. Just a little noisy.

Hi Ashley, I am not the original poster of this problem, was merely trying to clarify the actual method the OP used for his install, and certainly not endorsing it, lol.