Adding height to an existing garden fence

[ColinHardie]

Hi, I have moved into a new build property and the existing fence isn't that high and its style does not give much privacy.

The image below shows the fence style/height. I was just going to purchase longer planks and just screw them onto the fence, similar to my badly drawn shapes as follows...

So some advice on...

1. Screws or nails?
2. How high can I go (based in Scotland)?
3. OK to butt planks together or do I need to maintain a gap (for wind?)
4. How best to fill the top gap when I reach a post? Obviously some planks are going require cutting in. I have seen other fences in the estate that have attached a horizontal batten to the outside (at the top with some capping to finish it off), that allows a short plank to be screwed on the inside to fill the gap. Is this the best approach?
5. How best to approach the corner so as not to not look unfinished?
6. Tools needed to effectively do the job...I have the basics (drill, saw, spirit level etc). Thinking circular saw for cutting lengths?

Basically any advice for a newbie would be greatly appreciated.

Thanks
Colin

 

[Tigercubrider]

How tall is it? In England, 6 feet is the limit.
if it is windy, you can set it as a hit and miss, so the new timbers hide the gaps.
you could also just buy some screening roll.
This is reeds or similar material wired to form a wind break and privacy.