New Door opening in external wall advice

[goodwija1]

Hi,
New to the forum amd wondering if I could get a little bit of expert advise on a project I have underway.
I am currently in a the early stages of erecting a conservatory on the side of my house, which is c.1920. In order to erect the cons. I am going to need to make a new opening in the external wall toward the corner of the house and install a new external grade UPVC front door, the conservatory will then bolt over the centre of my existing fron door.
As I say I am in the early stages of the project and at this stage have a couple of questions in relation to the new installation of the front door.
I contacted BC with my intention and the inspector said that they may be an issue with the new opening dependant of wheather or not I have a clinker block type wall or not. He visited and looked under the render and confirmed that I have got a solid brick/rock type wall 9 inches thick and the opening would not be a problem, that being said brings me to my questions ( I have supplied a link to a picture of the house below )
What I need to do is create an opening right in the centre of an existing window, currently at the botom of the inside stairs, install a new lintel and fit a new upvc door. The door is going to need to be higher than the original door and steps built upto the door both inside and out, the reason for this is that the BC Inspector has said that I cannot go too close to the house corner to allow for support of the frame. The way in which I want to tackle this is:

1. Remove and brick up existing window opening
2. Grind hole above intended opening and install one strong boy and acro prop.
3. Grind out lintel opening ( same height as existing window lintel, so remove it and install new longer one )
4. Slide in Lintel, level and wait for mortar to set
5. Once all set, remove acro/strong boy
6. Cut out door way
7. Install New door frame, level, fix, foam fill and trim with cloaking ( Door opening outwards to enable un restricted opening from inside stair case).

Here are the questions I have.

1. What type of lintel will I need, or will I need to get a structural engineer in ?
2. Being that my existing walls are aparently solid, non cavity walls do I need to install an insulated cavity when I brick up the window, If not, can I just use breeze blocks and sit the lintel on them?
3. As far as the BC Inspector is concerned, at what stage will he want to inspect the work. Obviously I will need to consider the security factor of there being a hole in the house. I am hoping that I can fit lintel, door frame, door and foam filler leaving the lintel and area around door frame open for inspection.

link to pictures

http://www.hjsolutions.com/pix/cons/

I really appreciate any advise that can be offered.
Thanks James.

[stoneyboy]

goodwija1,
Unfortunately you link does not work.
1. lintol type will depend on what is supported above it and how close first floor joist are to the lintol.
2. form fill using solid blocks of the same type as are already installed.
3. BI will want to see the lintol.
end

[goodwija1]

Stoney boy,
I have edited the link above now so the pictures can now be seen.
Thanks very much for your help, One lother question, the lintel will be fitted directly underneath the top floor joists, also, have just spoken to BI and because I am limited to tight tolerances, I told him that I inteneded to install a prestressed concrete lintel. But he has advised me to "preferably" install an insulated lintel for solid masonry construction. That being added now poses a new problem as the catnic type I was looking at is a few inches taller than the concrete type, meaning I do not really have enough clearance for the door. That being said, I could solve this problem by moving the intended opening over a couple of hundred mm, but that would mean to maintain at least 150mm bearing each side of the lintel about 70-100mm would need to be grinded out of the solid blockwork in the butressing front wall, do you know if this is acceptable without compromising the structural makeup of the house.

Thanks again

[stoneyboy]

goodwija1,
I can't comment on the stability of your structure if it is modified.
Also I don't see any point in using an insulated lintol in a solid wall - use a PC lintol. Check the lintol can take the point loading from the joists.
end

[goodwija1]

Stoneyboy,
Once again, thanks for your response, I appreciate the advice and agree with you totally on the insulated lintol as the BI has advised that I can use solid light weight block work to brick up a window but has said I need to use an insulated Lintol that has o will bump the cost of the project up somewhat, I cant really see why the installation of a ps lintol compressed in the side wall would compromise anything but I want the BI to pass it.