timber cladding

[caseyjones1961]

Got a few questions about fitting some shiplap timber cladding (not hardwood or T&G) the cladding will be fitted horizontally to vertical 25x50 batons, should I fit horizontal batons at the top and bottom of the verticals to prevent insect/small animal infestation in the "cavity" behind the cladding or leave it open for ventilation?
Is it necessary to space the cladding horizontally and if so how do I go about spacing it....read about using matchsticks or similar which is easy at the ends of the cladding but not so easy at the centres...won't the centres "sag"?..cladding is in 3.9m lengths.
Finally....any advantage to pre-drilling the cladding and should I put 1 or 2 nails across the width(150mm) I'm planning to use annular ring shanks, hand hammered in.
Sorry for so many questions but just trying to get ahead of the game before I start...I usually find stuff out after I put the last nail in only to find I should've done something different!
Any tips/advice much appreciated.

 

[Deluks]

Leave the top and bottom open, the top can be clad right up to the roof overhang/soffit.
Fit insect mesh to the bottom, but it must be kept clear for airflow. You can use slightly smaller battens, 18mm thick is fine.

Spacing can be done manually, install from bottom to top, making sure each board is raised very slightly from the resting position.

Pilot drill is time consuming, but guarantees no splits. Ring shanks are a good choice, be sure to use stainless or sheradised, just the one nail across the width, trapping the board below. (See pic)

You can do 2 nails for the final top board, but drill the top one with a pilot hole a couple of mm bigger, just smaller than the nail head, for expansion.

 

[caseyjones1961]

Thanks for the speedy and comprehensive response Deluks....much appreciated