Flappy Bird Collision Detection Inaccurate C++ SFML

Question

I am learning to make 2d games with c++ using the SFML libraries. I am currently working on a flappy bird clone. Most of the functionality works (the pipes move and the bird jumps/falls); however, the collision detection is unacceptably inaccurate. The bird dies when it is exactly between the two pipes, where it should not. Here is the collision detection code:

  bool checkCollision(int x, int y, int w, int h, int xTwo, int yTwo, int wTwo, int hTwo){
    IntRect birdRect(x,y,w,h);
    IntRect pipeRect(xTwo,yTwo,wTwo,hTwo);

    return birdRect.intersects(pipeRect);
  }

  void logic(){
    if(bird->getY() + 45 > h-150){
      gameover = true;
    }

    int birdX = bird->getX();
    int birdY = bird->getY();
    int birdW = bird->getW();
    int birdH = bird->getH();

    for(int i=0;i<pipes.size();i++){
      int pipeX = pipes[i]->getX();
      int pipeY = pipes[i]->getY();
      int pipeW = 150;
      int pipeH = pipes[i]->getH();

      if(checkCollision(birdX,birdY,birdW,birdH,pipeX,pipeY,pipeW,pipeH)){
        cout<<i<<endl;
        gameover = true;
      }

    }

  } 

And if you need it, here are the bird and pipe functions:

class Bird{
private:
  //global variables
  int y;
  int originalY;
  int x;
  float velocityY;
  const float thrust = 30;
  float gravity;
  int screenH, screenW;
  const float w = 110.0;const float h = 80.0;
  Texture birdTexture;
private:
  //private functions

public:
  //public functions
  Bird(int grav, int width, int height){
    screenH = height;screenW = width;

    y = height/2; x = width/4;
    originalY = y;

    gravity = grav;

    velocityY = 0;

    birdTexture.loadFromFile("art/bird.png");

  }

  //inline functions
  inline int getY(){return y;}
  inline int getX(){return x;}
  inline int getW(){return w;}
  inline int getH(){return h;}

  void Update(){

    if(y+40 < screenH){//above ground
      velocityY += gravity;
    }else if(y+40 < screenH){//below ground
      y = screenH-40;
    }else{//on ground
      if (velocityY > 0 ){
        velocityY = 0;
      }
    }



    y += velocityY;

  }

  void Jump(){
    velocityY -= thrust;
    velocityY += pow(velocityY,2)*.015;

  }

  void Draw(RenderWindow& window){
    RectangleShape birdShape(Vector2f(w,h));
    birdShape.setPosition(x+w/2,y+h/2);
    birdShape.setTexture(&birdTexture);

    birdShape.setOutlineColor(Color::Black);
    birdShape.setOutlineThickness(2.0f);

    window.draw(birdShape);
  }
};

class Pipe{
private:
  //global variables
  int x,y;
  const float w = 150;
  float h;
  bool top;

  Texture topPipeTexture;
  Texture bottomPipeTexture;

private:
//private functions

public:
//public functions
  Pipe(int height, int screenW, int screenH, bool isTop){
    h = height;
    x  = screenW;
    top = isTop;
    topPipeTexture.loadFromFile("art/top pipe.png");
    bottomPipeTexture.loadFromFile("art/bottom pipe.png");
    if (top){
      y = h/2;
    }else{
      y = screenH - (h/2)-150;
    }
  }

  //inline functions
  inline int getX(){return x;}
  inline int getY(){return y;}
  inline int getH(){return h;}
  inline int getW(){return w;}
  inline bool isTop(){return top;}

  void Update(float speed){
    x -= speed;
  }

  void Draw(RenderWindow& window){
    RectangleShape pipeShape(Vector2f(w,h));

    if(top){
      pipeShape.setTexture(&topPipeTexture);
    }else{
      pipeShape.setTexture(&bottomPipeTexture);
    }

    pipeShape.setPosition(x,y-h/2);

    pipeShape.setOutlineColor(Color::Black);
    pipeShape.setOutlineThickness(2.0f);

    window.draw(pipeShape);
  }
};